“You must be in the wrong place!” — this was how my interview talk for a professorship in physics began more than twenty years ago. Since then, much has changed. Female physicists have become more visible, gender equality has become an important aspect of appointment procedures, funding programs, and scientific committees, and questions of work-life balance, dual careers, leadership, and fair...
Equal participation of highly qualified women in quantum technology has not yet been achieved. Although quantum technologies are considered key technologies and receive significant funding, women remain significantly underrepresented in related fields such as physics, computer science, and certain engineering disciplines.
Furthermore, the few women in these fields are often less visible than...
Dr. Isabel Barbosa is a Laser Engineer at Marvel Fusion, a DeepTech company based in Munich, aiming to commercialize fusion energy.
Isabel’s academic career focused on interdisciplinary research, with a Bachelor’s and Master’s degree in Chemistry and a PhD in Physics. Her current work at Marvel Fusion focuses on optical components, such as mirrors and gratings, for high-energy environments,...
In the last decade the physics of spin waves has regained interest in the emerging field of magnonics. In a magnonic device, the collective precession motion of spins in a ferromagnet permits to process information at low power consumption and high operation speed in a wide frequency range from GHz to THz. Spin waves present two important features: their frequency can be easily varied by...
TOPTICA Photonics SE is a leading provider of high-end laser systems for scientific and industrial applications, with technologies used in quantum technologies, biophotonics, materials processing, and metrology. The TOPTICA Group employs over 600 professionals across seven corporate entities.
In this talk, I will share my personal path from Physics studies at university into industry and...
Magnetic skyrmions, nanoscale chiral spin textures with particle-like behavior, are promising candidates for information storage and unconventional computing due to their robustness and efficient current-driven motion [1-3]. In Ta/CoFeB/MgO multilayers, we investigate the transition of current-driven skyrmion motion from creep, through depinning, to the viscous flow regime driven by a...
During the past decades, researchers have identified many factors crucial for the development of interests, ability self-concepts, and eventually career choice. Concurrently, practitioners have developed and implemented short- and long-term intervention programs to foster girls’ and young women’s interest in STEM fields (Science, Technology, Engineering, and Math). Some of these are...
We propose to combine Bose-Einstein condensation in higher Bloch bands and a driven-dissipative cavity-BEC system into a hybrid light-matter platform. Specifically, the condensate is trapped in a bipartite $s$–$p_x$–$p_y$ lattice, with a tunable energy offset. This enables a controlled population transfer from the $s$-orbital to the nearly degenerate $p_x$ and $p_y$ orbitals. The system forms...
As a PhD student I imagined research in industry to be very different than in academia. That certainly holds true for many companies. However, in a cutting-edge field like quantum computing, there are startups which pursue research questions which are actually very similar to those discussed at universities. neQxt is such a startup that offers positions where the daily activities are similar...
Over the past 30 years, tensor network techniques have been established as powerful tools in computational condensed matter physics. In one-dimensional quantum systems, one usually represents the many-body wave function as a matrix product state (MPS), a tensor network consisting of three-legged tensors, with individual tensors corresponding to the lattice sites in the system. This ansatz...
In non-centrosymmetric crystal structures with $D_{2d}$ or $S_4$ symmetry, anisotropic Dzyaloshinskii-Moriya interaction (DMI) stabilizes antiskyrmions which was recently confirmed experimentally [1,2]. In these materials, easy-axis anisotropy additionally stabilizes skyrmions and non-topological bubbles in certain ranges of external magnetic fields and lamella thicknesses. The competition...
Plötzlich ist viel gleichzeit los im Leben: Uniabschluss, Berufseinstieg, Karriereentwicklung, Familiengründung, um die Eltern kümmern, neue Freundschaften finden, sich als Paar nicht verlieren und das alles unter Zeitdruck und mit Schalfmangel. Kann man sich auf diese Expedition vorbereiten? Anhand meines beruflichen Weges möchte ich beschreiben, welche Ratschläge und Tipps mir geholfen...
Future quantum networks require interfaces that connect quantum processors over long distances. Superconducting quantum circuits are a leading platform for quantum computing, but operate with microwave-frequency signals that cannot be efficiently transmitted through optical-fiber networks (1, 2). Optical photons, by contrast, are well suited for low-loss communication over long distances and...
Entangled photon pair sources are essential resources for quantum technological applications. AlGaAs Bragg reflection waveguides are promising platform for such sources due to their high nonlinear coefficient, room temperature operation, and non-birefringent nature [1]. By using a type-II SPDC process, the down-converted photons are orthogonally polarized, and the generated photon pairs are...
Mit diesem Beitrag stellen wir Euch den Arbeitskreis Chancengleichheit (AKC) vor, eine fachübergreifende Vereinigung innerhalb der Deutschen Physikalischen Gesellschaft (DPG) mit über 850 Mitgliedern. Das Ziel des AKC ist die Verbesserung der Rahmenbedingungen und Strukturen für Frauen in der Physik zur Erreichung von Chancengleichheit in Ausbildung und Beruf. Hierzu gehört auch die jährlich...
We report on the electronic and topological properties of ZrTe₅ flakes synthesized via chemical vapor transport (CVT). Mechanically exfoliated ZrTe₅ flakes with nominal thicknesses ~100 nm are transferred onto pre-fabricated Pt contacts with 1-3-3-1 Hall bar geometries on SiO₂/Si sugbstrates. Using ac phase-locked low-/high-magnetotransport measurements, a distinct longitudinal resistance peak...
White Etching Cracks (WEC) are complex crack networks that cause premature damage under rolling contact fatigue. Hydrogen is suspected of promoting crack formation, but its exact role remains unclear. Crack initiation and propagation are still insufficiently understood because of the interaction between microstructure, inclusions, and crack evolution.
A major challenge is that conventional...
Since 2015, the Gender Equity Task Force of the international society for optics and photonics (SPIE) has been working to identify how the professional environment and culture of the optics and photonics community can better enable equal opportunities, rewards, and recognition for its members, independent of gender. The Task Force focuses on identifying and recommending specific steps our...
In this work, we explore how a magnon Bose–Einstein condensate (BEC) responds to external perturbations and how its stability and lifetime can be controlled. The magnon BEC is created by populating the magnon gas above the thermal equilibrium level using pulsed parallel parametric pumping. A second pulse at a different frequency—with its parametric excitation frequency tuned from below the...
The investigation of superconducting Josephson junctions requires low-noise and configurable DC measurement setups capable of resolving superconducting features. To improve the experimental capabilities of a Bluefors® dilution refrigerator, a modular upgrade of the Fast Sample Exchange (FSE) puck was developed, focusing on flexible wiring, integrated filtering, and improved sample...
In the face of 28 million tonnes of spent refractories annually, recycling and upcycling strategies for MgO-C refractories are crucial to more sustainable and environmentally friendly materials management in high-temperature industries. The research training group GRK 2802 funded by the German Research Foundation (DFG) investigates two core ideas addressing the use of spent MgO-C.
The...
Atomic Force Microscopy (AFM) is a versatile tool for studying biological systems from the single cell to the nanoscale. By combining tailored surface functionalization, single-cell force spectroscopy, FluidFM-based cell manipulation, and correlative AFM–confocal microscopy, we establish an experimental framework to investigate biological interfaces and microbial adhesion.
Silicon...
Nanodiamonds with crystal defects have gained increasing importance in biological and chemical applications [1]. Most prominent are fluorescent nanodiamonds (FNDs) with nitrogen-vacancy (NV) centers due to their unique properties such as high photostability, chemical inertness and sensitivity towards magnetic and electric fields [2,3]. These properties make them highly suitable for the in-situ...
Functional materials embedded in three-dimensional photonic microstructures offer new routes for advanced photonic devices. We present two different approaches towards such devices: the incorporation of colloidal quantum dots (QDs) into 3D-printed microstructures for hyperspectral sensing applications, and the integration of the nonlinear organic molecule DDMEBT into 3D microstructures to...
ZnO is a prototypical wide-band-gap material with long-lived excitons, making it a central platform for modern optoelectronic and catalytic technologies, especially for investigating exciton-related phenomena [1]. Excitons—bound electron–hole pairs that can exist in various forms near the surface, significantly shape the material’s optical and electronic response and play an essential role in...
Group-IV color centers in diamond are well known for their suitability as nodes within quantum networks due to their excellent spin and optical coherence. The tin-vacancy center (SnV-) in particular shows Fourier limited linewidths, a small inhomogeneous distribution of emission wavelengths, and excellent long-term spectral stability [1-3]. The latter two of which have been observed for deep...
Quantum-based approaches are emerging as a promising alternative for high-accuracy pressure metrology, offering direct SI traceability and the potential to reduce measurement uncertainties. This work presents the development and improvement of a Fabry–Perot refractometer as part of ongoing efforts to realize quantum-based pressure standards. The system was designed, assembled, and used to...
Iridium complexes have highly interesting photochemical, photophysical and catalytic properties. They are used for example in organic light-emitting diodes (OLEDs), organic solar cells and automotive exhaust catalysts.[1,2,3] Iridium complexes have also been used to initiate "water oxidation reactions“.[4,5] They also hold promise as photosensitisers and photocatalysts for directed...
The Fluorescence Detector (FD) of the Pierre Auger Observatory provides energy measurements of primary cosmic rays that are largely independent of specific interaction models. These measurements are crucial for calibrating the energy reconstruction of the Surface Detector. Consequently, the accuracy of the FD energy calibration plays a key role in the systematic uncertainties associated with...
Physics continues to be regarded as a male-dominated subject with a ‘leaky pipeline’ throughout the career progression – from the beginning of undergraduate studies right through to a professorship. Since 2021, the "Mehr für Physikstudentinnen" ("More (for) Female Physics Students") project at the Department of Physics and the Gender Equality Office at Marburg University has been addressing...
Quantum error correction protects fragile quantum information by encoding it non-locally across many physical qubits, and stabilizer measurements, the syndromes used to diagnose errors, are performed continuously on any error-corrected device. In this work we ask what this routinely collected data certifies about entanglement, at no additional measurement cost. Focusing on the seven-qubit...
Carola Meyer, Dagmar Paarmann, Agnes Sandner,
Beate Klösgen ( für die AKC-Kommission)
Der Arbeitskreis Chancengleichheit (AKC) wurde 1998 als ein Arbeitskreis
innerhalb der Deutschen Physikalischen Gesellschaft e.V. (DPG) gegründet.
Das Ziel des AKC ist die Verbesserung der Chancengleichheit für alle
Physiker:innen, beginnend auf allen Ebenen der DPG und im Sinne der
umfassenden...
Der Arbeitskreis Chancengleichheit (AKC) der DPG hält im Rahmen der DPT eine Informationsveranstaltung und seine jährliche Mitgliederversammlung ab. Alle Mitglieder sowie auch weitere Interessierte sind herzlich zur Teilnahme eingeladen!
Die AKC-Kommission berichtet über ihre Arbeit des vergangenen Jahres und gibt eine Vorschau auf geplante Projekte und Veranstaltungen. Alle Anwesenden sind...
Organoids and cancer spheroids are often too opaque for optical imaging by single-sided illumination. Rotating the sample for multi-angle illumination solves this, enabling 3D tomographic reconstruction of the refractive index. Optical and acoustic forces can both manipulate microscopic samples in suspension without contact, but heavier samples require acoustic levitation. Tuning standing MHz...
Molecular motors are the tiny building blocks of life and are key to a wide range of biological functions at the molecular level. They change their shape upon interacting with a substrate molecule. Identifying these conformational changes is critical to understanding the intricate catalysis and signalling processes of a cell. Since the lateral dimensions of molecular motors are two orders of...
Global warming requires humanity to reduce atmospheric CO2 significantly - and fast. Chemically, CO2 reduction (i.e. electron attachment) is a vital step for its conversion to less harmful or even useful carbon-based products. One approach to capture CO2 is to freeze it at cryogenic temperatures before chemical modification. Whether or not single electron transfer to CO2 is feasible at these...
Looking back on my career, I can say that at the beginning I was not expected to be where I am now. Each stage - from university studies in materials science and engineering, doctoral research in metallurgical physics, and to industry work in cryogenics and quantum computing grew from opportunities, curiosity, and skills developed in the previous stages. My teachers, supervisors and colleagues...
The proper function of cells is directly related to the subcellular compartmentalization and spatial distribution of a broad range of molecular species, from enzymes to metabolites and signaling molecules. Determining the spatial distribution of biomolecules within cells is therefore crucial for understanding fundamental cellular mechanisms; yet there is a lack of technologies capable of in...
Spintronics, the way forward to device miniaturization, leverages electron spin rather than charge. Though inorganic materials were predominantly given more attention in spin transport studies, organic semiconductor (OSC)/magnetic hybrid interfaces are quickly gaining interest, owing to the flexibility, scalability, and structural tunability of organic materials. Here, we probe the effect of...
A traditional physics degree equips researchers with the knowledge and critical thinking skills to solve fundamental problems across a diverse range of fields, including quantum mechanics, optics, astrophysics, and solid state physics. However, many real-life problems cannot be solved by hand and must be recast into a format that can be processed by a computer. With rapid advancements in...
The man-made climate crisis is, irrefutably, one of the greatest challenges of the 21st century. Scientists across the entire globe and every research field have put forth possible solutions in an effort to mitigate its effects and slow its progress. The MOST concept, short for “Molecular Solar Thermal”, is focused on the development of organic photoswitches that transform into high-energy...
Functional metallic surfaces with tailored wettability are of increasing interest for applications requiring enhanced corrosion resistance, self-cleaning behaviour, and reduced fouling. While laser texturing and chemical functionalization are established approaches for producing hydrophobic metallic surfaces, their combined effect remains poorly understood. Addressing this challenge is...
This contribution offers a personal account of the transition from academic physics research to industry. I share my experience of moving into consulting, where I currently work on risk management for financial institutions, an interdisciplinary field that has gained particular relevance in today’s environment of geopolitical uncertainty and volatile international markets.
The talk reflects...
Resonant scattering is central to atomic, molecular, and optical physics and provides a powerful tool for controlling interactions in ultracold quantum gases. In ultracold atomic systems, magnetically tunable Feshbach resonances enable precise control of the interaction strength. Building on our recent demonstration that periodic magnetic-field modulation Floquet-engineers additional Feshbach...
Quantum phenomena in condensed matter that are difficult to access experimentally can be investigated using photonic analog quantum simulation, where classical light emulates quantum dynamics. In coupled optical waveguide arrays, evanescent coupling mimics electronic tunneling, enabling the study of tunable band structures and topological effects. Topological materials exhibit topologically...
In this talk, I will explore the often nonlinear nature of careers in physics, challenging the traditional notion of a single, predefined professional trajectory. Drawing from my own experiences moving between academia and industry, I will highlight how unexpected opportunities, personal decisions, and changing priorities have influenced my career path.
Through candid reflections on...
Quantum technologies are reshaping our understanding of computation and communication, promising capabilities fundamentally beyond classical limits. Among the many physical platforms under investigation, solid-state emitters stand out for their potential scalability and on-chip integrability — making them attractive building blocks for future quantum network nodes.
Color centres in diamond...
Chirality is omnipresent in nature, bridging magnetic and molecular spin phenomena. At the core of this connection lies the chiral-induced spin selectivity (CISS) effect, describing the highly efficient generation of spin polarized currents in chiral molecules. Despite extensive experimental evidence, the underlying mechanisms of CISS remain debated. Here, we explore how chirality is directly...
Plant viruses represent highly uniform and genetically programmable nanoscale building blocks for bottom-up nanotechnology. Over the past years, we have used the icosahedral Tomato Bushy Stunt Virus (TBSV, diameter ~ 30 nm) as a versatile platform for the fabrication of ordered virus-based nanostructures. This work summarizes a research line developed in our group from virus self-assembly and...
Nitrogen Vacancy (NV) centers in diamond have emerged as versatile quantum sensors, enabling nanoscale detection of magnetic and electric fields, temperature shifts, strain and chemical environments under ambient conditions. The unique spin properties of NV centers combined with the exceptional properties of diamond provide a powerful platform for investigating physical, chemical, and...
The International Year of Quantum Science and Technology (2025) highlighted not only the scientific progress of quantum technologies but also the need to accelerate their transition from research laboratories into practical applications. To better understand the factors that enable or hinder this transition, the Working Group on Equal Opportunities (AKC) of the German Physical Society (DPG)...
In this talk, I will present the feasibility of using the Grover algorithm to reconstruct gene regulatory networks from bioinformatics data. For this purpose, we modify the Grover algorithm to use multiple distinct oracles belonging to different cells and different cell types. We apply the algorithm to simulated and real bioinformatics datasets demonstrating its applicability to noisy data.
The phenomenon of the chiral-induced spin selectivity (CISS) effect refers to the spin-polarization of electrons in the presence of chiral molecules or structures. Their potential for high polarization efficiencies makes hybrid chiral molecule / magnet devices promising for efficient and sustainable spintronic devices. Despite various experimental reports on different facets of the CISS...
Despite growing awareness of structural inequalities in physics, unconscious bias remains a persistent challenge in selection processes – from awards and speaker invitations to hiring. Gender disparity, institutional concentration, and career-stage imbalance often remain invisible until after decisions are made.
This talk introduces Equity Lens, a prototype developed under the Working...
The essential nutrient phosphorus is mined in only a few regions of the world and is mainly processed into fertilizers distributed worldwide. Its limited availability, together with increasing geopolitical uncertainties, highlights the need for a more resilient and circular phosphorus supply. Recovering phosphorus from wastewater treatment plants (WWTPs) is a promising approach to closing the...
Monocrystalline diamonds (MCD) embedded with color centers have emerged as promising candidates for applications in quantum optics, namely sensing. Specifically, negatively-charged silicon vacancy centers (SiV) stand out as ideal due to their narrow zero phonon line (ZPL) at 738 nm, coupled with a high Debye-Waller factor of up to 70 %. However, their application remains hindered by the...
Studies have repeatedly demonstrated that diverse teams lead to increased creativity, productivity and innovation - a phenomenon that can be observed in both academic and industrial settings. However, substantial gender imbalances persist in physics: Although the number of women studying physics in Central Europe has grown steadily over the last years, they remain underrepresented at senior...
In addition to being an ideal tool for imaging and manipulating atoms and molecules on surfaces, the potential of the scanning tunneling microscope (STM) for high-resolution spectroscopy has been recognized in the fields of single-molecule physics, magnetism, and superconductivity.
Here, we use the STM to resolve the interplay of magnetic atoms and molecules with superconducting...
Dr. Gesa Welker, Eindhoven University of Technology
Quantum sensing is one of the pillars in the currently ongoing second quantum revolution. In my talk, I will explain how impurities in diamond, quantum sensors of just the size of an atom, can detect extremely tiny magnetic fields. Such so-called color centers in diamond are used for many applications, they have e.g. been used to map the...
The Eigenstate Thermalization Hypothesis (ETH) provides one of the main paradigms for understanding the emergence of thermal behavior in isolated quantum many-body systems. Recent developments in quantum dynamics have highlighted that a deeper understanding of quantum chaos and thermalization requires going beyond the standard ETH ansatz by considering higher-order correlations, a framework...
Search for Hidden Particles (SHiP/NA67) is a new general-purpose, high-intensity beam dump experiment at CERN approved in 2024 and designed to explore the largely uncharted domain of feebly interacting particles with masses from 100 MeV to a few GeV. These particles are predicted by a large number of theories beyond the Standard Model capable of explaining phenomena such as dark matter,...
Reliable non-volatile memories capable of operating under radiation are essential for harsh-environment applications, such as microsatellites in low Earth orbit (LEO). Radiation-tolerant devices can improve mission reliability while reducing system complexity and the need for additional radiation mitigation techniques. Resistive random-access memory (RRAM) is a promising candidate due to its...
Optically addressable spin systems, such as nitrogen-vacancy (NV) centers in diamond, have been widely studied for quantum sensing applications. Recently, our group demonstrated two novel quantum sensing platforms based on naturally occurring spin defects in boron nitride nanotubes (BNNTs) (1,2). These defects combine high surface area with omnidirectional spin control—key features that...
The detectors of the Pierre Auger Observatory, primarily designed to observe ultra-high energy cosmic rays and identify their sources, simultaneously take advantage of their sensitivity and large coverage area to detect transient luminous events and terrestrial gamma-ray flashes (TGFs), atmospheric phenomena closely linked to lightning and thunderstorms. Owing to their sensitivity to...
Rare-earth ions in crystalline hosts are promising candidates for quantum memory applications, offering long-lived nuclear spin states and frequency compatibility with superconducting quantum circuits. A key factor limiting spin coherence in these systems is the interaction of the electron spin with the surrounding nuclear spin bath, the superhyperfine (SHF) interaction, which can be also...
Fluctuations of conserved charges such as baryon number, electric charge, and strangeness are effective probes of the QCD phase diagram. Their higher-order cumulants are particularly sensitive to critical phenomena and remain an important focus of current heavy-ion research.
In this work, an exploratory study of strangeness fluctuations in Ag+Ag collisions at $\sqrt{s_{NN}} =...
Accurate photometric calibration of astronomical photographic plates remains a fundamental challenge in astronomy due to the mismatch of spectral sensitivities of photographic plates and pass bands of modern calibration catalogs.
We intend to derive consistent natural magnitudes for celestial sources within the intrinsic photometric systems of astronomical photographic plates by using Gaia...
The combination of plasmonic nano-antennas and atomically thin semiconductors offers an ideal platform to explore light matter coupling on the nanoscale. One reason is that the natural Bohr radius of excitons in these materials is in the range of a few nanometers and therefore significantly smaller than the optical diffraction limit, i.e. the resolution of standard far-field optical setups. In...
Compact and efficient light sources are essential for integrated photonic circuits, yet their direct integration with silicon-based platforms remains challenging due to the inefficient light emission of silicon. III–V semiconductor nanowires offer a promising route towards nanoscale light sources, combining a small footprint and efficient strain relaxation with the direct band gap required for...
The combination of scanning transmission X-ray microscopy (STXM) and X-ray fluorescence (XRF) analysis enables the simultaneous acquisition of elemental distribution maps and multiple transmission imaging modes. In the soft and tender X-ray range, this combination has become an increasingly powerful tool for materials science, biomedical, and environmental research.
We present the portable...
A successful and effective global energy transition requires an enormous expansion of renewable energy technologies at the terawatt scale. Perovskite solar cells have high potential to address this challenge as they are offering high efficiency, cost-effective fabrication and material flexibility. Alongside performance, sustainable development also requires a consistent focus on scalability....
Scanning nitrogen-vacancy (NV) magnetometry is a powerful technique for nanoscale magnetic imaging. In this approach, the conventional atomic force microscopy tip is replaced by a diamond nanopillar containing a single NV center, which serves as a highly sensitive local magnetic field sensor. By scanning the NV center over a sample, the magnetic stray field can be mapped with high spatial...
Are the spectroscopic properties of plasmon- and photon-induced carriers fundamentally different? This question is crucial for advancing plasmonic energy conversion. Initial studies have suggested characteristic energy and momentum distributions for the photoemission of both bulk plasmon resonances and surface plasmons. For surface plasmons, however, the separation of plasmon and...
Germanium has emerged as a promising platform for superconductor–semiconductor hybrid devices [1,2] due to its compatibility with existing CMOS technology, high carrier mobility [3], and a relatively strong spin–orbit coupling [4]. A critical requirement for such hybrid systems is the realization of a transparent and well-defined interface between the superconductor and the semiconductor at...
Laura Rojo Guerrero1*, Niklas Schmidt1, Elena Blundo1,2, Jonathan J. Finley1,3
1Walter Schottky Institut and TUM School of Natural Sciences, Technische Universität München, Am Coulombwall 4, Garching, Germany
2Physics Department, Sapienza University of Rome, 00185 Rome, Italy
3Munich Center for Quantum Science and Technology (MCQST), Munich, Germany 1
Department of Nanoscale Research,...
Sukhjit P. Singh,1 Elnaz Bazzazi,
2, ∗ Diego N. Bernal-Garc´ıa,1 Simon White,1 Hassan Jamal Latief,3 Alison
Goldingay,3 Sven Rogge,3 Sergei Slussarenko,1 Farzad Ghafari,1 Emanuele Polino,1 and Nora Tischler1
1Queensland Quantum and Advanced Technologies Research Institute,
Centre for Quantum Computation and Communication Technology,
Griffith University, Yuggera Country, Brisbane,...
Approximately 80\% of global energy is currently lost as low-grade waste heat (300–600 K). While solid-state thermoelectric (TE) generators present a promising solution for waste heat recovery, conventional high-efficiency TE materials are typically toxic and incompatible with standard Complementary Metal-Oxide-Semiconductor (CMOS) manufacturing, severely hindering their large-scale industrial...
Ultraviolet (UV) photonic integrated circuits (PICs) have many interesting applications, such as biochemical sensing, atomic clocks, and UV Raman spectroscopy. For realizing PICs in the UV spectral range, materials with a large bandgap are required to facilitate low optical losses. One exciting option is AlGaN as it allows the monolithic integration of AlGaN based UV light emitting diodes...
We characterize the lowest optically active excitation of a one-dimensional extended Hubbard chain with on-site repulsion $U_0$ and nearest-neighbor repulsion $U_1$. Two complementary natural-orbital diagnostics disentangle the character of the excitation: the one-particle-one-hole (1p1h) weight $W_{1p1h}$, which measures how completely a single particle-hole picture accounts for the...
Nina Miller, and Johanna Eichhorn —
Physics Department, School of Natural Sciences, Technical University
of Munich, Am Coulombwall 4, 85748 Garching, Germany
Earth-abundant electrocatalysts—such as transition metal oxyhydroxides and oxides—have emerged as promising and cost-effective alternatives to noble metals for water-splitting applications. To be viable, these electrocatalysts must...
PUNCH4NFDI unites Germany's astroparticle, particle, astrophysics, hadron, and nuclear physics communities to collaboratively develop and implement infrastructures that enable FAIR data management across the full research data lifecycle within an integrated digital ecosystem. Over its first funding phase, the consortium established the core building blocks of this ecosystem: the concept of...
An ensemble of atoms coupled to a common electromagnetic environment displays collective effects, such as sub- and superradiance. These can be harnessed experimentally in cold atom array experiments, where the atoms are tightly confined and close to the motional ground state. This requires to treat atomic motion, both quantum and thermally induced, as a quantum degree of freedom which couples...
The large ground-state nuclear-spin manifold of fermionic alkaline-earth atoms is an attractive resource for quantum information, thanks to its weak coupling to external perturbations. However, detection schemes that combine fast state-resolved imaging beyond two states with single-atom resolution remain a significant challenge. State-of-the-art quantum simulators with single-particle and spin...
When a metal is irradiated with an ultrashort optical laser pulse, the electrons become excited, disturbing the electron distribution into a state far from equilibrium. The subsequent relaxation dynamics determine how the absorbed energy is redistributed within the electronic system and transferred to the lattice, making electron thermalization a key process in ultrafast laser-matter...
Humans have a natural instinct to characterize objects and sort them into categories. Topology builds on this idea in a particularly unusual way: everyday objects can be classified according to properties that survive continuous deformation. A coffee mug and a doughnut, for example, are topologically equivalent because each has one hole.
Similar ideas have become remarkably powerful in...
Quantum mechanics lies at the heart of many fascinating phenomena in condensed matter physics. One prominent effect is superconductivity, where fermionic electrons pair up to form composite bosons. Their collective quantum coherence gives rise to superconductivity and closely related superfluid behavior.
Ultracold atoms provide a powerful platform for studying these phenomena on a...
Accurately computing the electronic energy of molecular reactants and during chemical reactions is the central challenge of quantum chemistry. Unlike mean-field methods such as Hartree-Fock or Kohn-Sham density functional theory, configuration interaction (CI) methods exactly calculate the repulsive interaction between electrons based on a many-particle wave function rather than relying on...
Rydberg atoms provide electric dipole–allowed transitions that span from optical to microwave frequencies, combining optical control with strong, tunable coupling to microwave-frequency solid-state systems. This makes them a powerful candidate for interfacing atomic ensembles with on-chip electromechanical devices. In this work, we study such an interface between Rydberg atoms and a...
Understanding the full parameter dependence of microscopic structure
in active matter remains a central challenge, particularly for strong activity
and high density, where simulations become increasingly expensive. Here,
we present a data-driven approach that learns radial and angular correla-
tions in terms of the pair-correlation function g$(r,\theta)$ of passive and active
Brownian...
Quantum walks provide a powerful platform for exploring non-classical transport phenomena and for designing controllable quantum dynamics in discrete systems. Here, we investigate the transport properties of a one-dimensional discrete-time quantum walk driven by a three-qubit Greenberger–Horne–Zeilinger (GHZ) entangled coin state, focusing on the contrasting effects of position-dependent (PD)...
Quantum computers promise new ways of solving problems that are difficult for classical computers, but their practical realization requires extremely precise control of quantum systems. In this talk, I will introduce the general challenge of controlling quantum devices and explain why reliable quantum operations are essential for scalable quantum computing. I will then present a new approach...
In the quantum computation era, the need of controlling the coherence lifetime of open quantum systems has increased considerably, making decoherence a critical topic. Quantum Darwinism (QD), a concept popularized by W. Zurek [1], can be viewed as a special case of decoherence with unique characteristics and can shed some light on the quantum-to-classical transition. In this scenario, nearly...
When multiple harmonic oscillators are coupled, they exhibit normal modes, which can be either delocalized or localized. The delocalized modes are used to exchange information between qubits in a Paul trap for quantum information processing, while localized modes can be used for frequency-resolved addressing. In this work, we observe both delocalized and localized normal modes depending on...
The goal of quantum key distribution is to establish a secure key between two or more parties. Depending on the exact task, different protocols are available. In the context of multiple parties, for example, we can distribute a common secret key among all participating parties [1]. Another task is to anonymously distribute a key between a subset of parties [2]. Both examples require...
Scattering-type scanning near-field optical microscopy (s-SNOM) and nanoscale infrared point spectroscopy (nano-FTIR) are powerful techniques for nanoscale optical mapping of various material properties. Both rely on elastic light scattering from an atomic force microscope tip illuminated by either monochromatic or broadband laser light. This metallic tip acts as an optical antenna,...
Two-dimensional transition-metal dichalcogenides (TMDs) are atomically thin semiconductors that exhibit strong excitonic effects, high optical nonlinearities, and valley-contrasting optical selection rules. In monolayer TMDs, circularly polarized light selectively addresses the inequivalent K and K′ valleys, enabling optical initialization and readout of the valley degree of freedom. These...
Rare-earth ions exhibit exceptional magnetic and optical properties, making them attractive systems for applications in quantum information science. While significant progress has been achieved in the storage of optical quantum states, the direct storage and coherent manipulation of microwave quantum states remains an important open challenge.
Here, we investigate broadband control of...
Binary group IV-VI chalcogenides, like SnTe, GeTe and SnSe, are of great scientific interest due to their diverse possible applications ranging from thermoelectrica to phase change memory. As possible origin of these remarkable properties, the interatomic bonding is center of an ongoing scientific debate. All binary group IV-VI compounds exhibit an average number of five valence electrons per...
This talk explores entrepreneurship as a viable and rewarding career path for women in physics — one that's often underrepresented in traditional academic career narratives. Drawing on experience in quantum technology venture building , the talk will help attendees think about their own PhD work through a commercial lens: how to recognize when their research might have real-world applications,...
We present a joint experimental and theoretical study of a ratchet implemented in arrays of evanescently coupled plasmonic waveguides with tailored losses. In this setup the time-periodic dissipation is the only active mechanism and notably, we find better rectified transport and lower losses in the transmitted signal with increased local dissipation. Using Floquet theory, we uncover a driving...
Hybrid superconductor-semiconductor devices are of interest for various applications in quantum physics – they can host different types of qubits or can be used for compact, low-noise, cryogenic electronics elements such as parametric amplifiers [1]. As semiconductor, we employ strained germanium quantum wells embedded in planar silicon-germanium heterostructures. Germanium was shown to be a...
Prof. Dr. Sibylle Günter,
Max-Planck-Institut für Plasmaphysik Garching und Greifswald
Der nahezu unbegrenzte, weltweit verfügbare Brennstoff sowie seine äußerst günstigen Sicherheitseigenschaften machen die Kernfusion zu einer äußerst attraktiven Alternative zur Kernspaltung. Dank ihres vergleichsweise geringen Flächenbedarfs eignet sie sich besonders für die Energieversorgung von...
