A5065157405- Quantum and electron transport phenomena
- Topological Materials and Phenomena
- Physics of Superconductivity and Magnetism
- Graphene research and applications
- Magnetic and transport properties of perovskites and related materials
- Electronic and Structural Properties of Oxides
- Advanced Condensed Matter Physics
- Rare-earth and actinide compounds
- Advanced Thermoelectric Materials and Devices
- Iron-based superconductors research
- Magnetism in coordination complexes
- Organic and Molecular Conductors Research
- Advanced Thermodynamics and Statistical Mechanics
- 2D Materials and Applications
- Surface and Thin Film Phenomena
- Thermal Expansion and Ionic Conductivity
- Quantum optics and atomic interactions
- Heusler alloys: electronic and magnetic properties
- Polymer crystallization and properties
- Theoretical and Computational Physics
- Crystallography and Radiation Phenomena
- Phase-change materials and chalcogenides
- Superconducting and THz Device Technology
- Gyrotron and Vacuum Electronics Research
- Quantum many-body systems
Max Planck Institute for Chemical Physics of Solids
2018-2025
University of Bonn
2023-2025
Helmholtz-Zentrum Dresden-Rossendorf
2024-2025
ETH Zurich
2016-2022
TU Dresden
2022
Max Planck Society
2020
Centrum Badań Molekularnych i Makromolekularnych Polskiej Akademii Nauk
2016
Polish Academy of Sciences
2016
Solid State Physics Laboratory
2015
Lodz University of Technology
2012
The quantum Hall effect (QHE) is traditionally considered a purely two-dimensional (2D) phenomenon. Recently, three-dimensional (3D) version of the QHE has been reported in Dirac semimetal ZrTe5. It was proposed to arise from magnetic-field-driven Fermi surface instability, transforming original 3D electron system into stack 2D sheets. Here, we report thermodynamic, thermoelectric and charge transport measurements on ZrTe5 regime. measured thermodynamic properties: magnetization ultrasound...
Abstract Interacting electrons confined to their lowest Landau level in a high magnetic field can form variety of correlated states, some which manifest themselves Hall effect. Although such states have been predicted occur three-dimensional semimetals, corresponding response has not yet experimentally observed. Here, we report the observation an unconventional quantum limit bulk semimetal HfTe 5 , adjacent effect single electron band at low fields. The additional plateau-like feature...
Oscillations of conductance observed in strong magnetic fields are a striking manifestation the quantum dynamics charge carriers solids. The large carrier density typical metals sets scale oscillations both electrical and thermal conductivity, which characterize Fermi surface. In semimetals, transport at low-charge is expected to be phonon dominated, yet several experiments observe giant transport. This raises question whether there an overarching mechanism leading sizable that survives...
By employing highly sensitive millikelvin SQUID magnetometry, the magnitude of Curie temperature as a function Mn concentration x is determined for thoroughly characterized Ga1-xMnxN. The interpretation results in frame tight binding theory and Monte Carlo simulations, allows us to assign spin interaction ferromagnetic superexchange benchmark accuracy state-of-the-art ab initio methods predicting magnetic characteristics dilute insulators.
Strong electron correlations lead to a variety of distinct ground states, such as magnetism, charge order or superconductivity. Understanding the competitive cooperative interplay between neighbouring phases is an outstanding challenge in physics. CeRhIn5 prototypical example heavy-fermion superconductor: it orders anti-ferromagnetically below 3.8 K, and moderate hydrostatic pressure suppresses anti-ferromagnetic inducing unconventional Here we show evidence for phase transition state akin...
The half-Heusler rare-earth intermetallic GdPtBi has recently gained attention due to peculiar magnetotransport phenomena that have been associated with the possible existence of Weyl fermions, thought arise from crossings spin-split conduction and valence bands. On other hand, similar observed in intermetallics often attributed interaction itinerant carriers localized magnetic moments stemming $4f$ shell element. In order address origin GdPtBi, we performed a comprehensive study...
The quantum limit (QL) of an electron liquid, realised at strong magnetic fields, has long been proposed to host a wealth strongly correlated states matter. Electronic in the QL are, for example, quasi-one dimensional (1D), which implies perfectly nested Fermi surfaces prone instabilities. Whereas typically requires unreachably topological semimetal ZrTe5 shown reach fields only few Tesla. Here, we characterize up 64 T by combination electrical-transport and ultrasound measurements. We find...
We introduce a new stress dilatometer with exactly the same size and mass as world’s smallest miniature capacitance (height × width depth = 15 14 mm3, mass: 12 g). To develop this device, only single part of most recently developed mini-dilatometer, so-called “body,” needs to be replaced. Therefore, mini-dilatometer an interchangeable body can used for high-resolution measurements thermal expansion magnetostriction without large stress. also report two novel applications both cell types. Our...
Properties of the depleted Heisenberg spin ladder material series $({\mathrm{C}}_{7}{\mathrm{H}}_{10}\mathrm{N}{)}_{2}{\mathrm{Cu}}_{1\ensuremath{-}z}{\mathrm{Zn}}_{z}{\mathrm{Br}}_{4}$ have been studied by combination magnetic measurements and neutron spectroscopy. Disorder-induced degrees freedom lead to a specific response, described in terms emergent strongly interacting ``spin island'' objects. The structure dynamics islands is high-resolution inelastic scattering. This allows us...
In this study, we report on the observation of de Haas-van Alphen-type quantum oscillations (QO) in ultrasound velocity NbP as well `giant QO' attenuation pulsed magnetic fields. The difference QO amplitude for different acoustic modes reveals a strong anisotropy effective deformation potential, which estimate to be high $9\,\mathrm{eV}$ certain parts Fermi surface. Furthermore, natural filtering frequencies and tracing individual Landau levels limit allows more detailed investigation...
The compound ${\mathrm{ZrTe}}_{5}$ has recently been connected to a charge-density-wave (CDW) state with intriguing transport properties. Here, we investigate quantum oscillations in ultrasound measurements that microscopically originate from electron-phonon coupling and analyze how these would be affected by the presence or absence of CDW. We calculate phonon self-energy due coupling, there deduce sound-velocity renormalization sound attenuation. find theoretical predictions for metallic...
Real-world topological semimetals typically exhibit Dirac and Weyl nodes that coexist with trivial Fermi pockets. This tends to mask the physics of relativistic quasiparticles. Using example ZrTe _5 <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:msub><mml:mi /><mml:mn>5</mml:mn></mml:msub></mml:math> , we show strain provides a powerful tool for in-situ tuning band structure such all pockets are pushed far away from energy, but only certain range Van der Waals...
The quasi-quantized Hall effect (QQHE) is the three-dimensional (3D) counterpart of integer quantum (QHE),exhibited only by two-dimensional (2D) electron systems. It has recently been observed in layered materials, consisting stacks weakly coupled 2D platelets that are yet characterized a 3D anisotropic Fermi surface. However, it predicted version QHE should occur much broader class bulk regardless underlying crystal structure. Here, we compare observation plateau-like features conductivity...
Using a combination of low-temperature nanocalorimetry and x-ray diffraction we identify three temperature regimes characterized by distinct Na ordering patterns (low up to 290 K, intermediate 290--340 high above 340 K). Through freezing-in these establish the two key roles sodium intercalation plays in formation magnetic ground state: supplying proper electron count for in-plane ferromagnetic interaction through 3D providing interplane antiferromagnetic exchange path.
Using a combination of neutron scattering, calorimetry, quantum Monte Carlo simulations, and analytic results we uncover confinement effects in depleted, partially magnetized spin ladders. We show that introducing nonmagnetic impurities into ladders leads to the emergence new characteristic length $L$ otherwise scale-free Tomonaga-Luttinger liquid (serving as effective low-energy model). This universal $LT$ scaling staggered susceptibilities. Comparison simulation with experimental phase...
We analyze the transport properties of curved, three-dimensional graphite samples in strong magnetic fields. Focusing on a millimeter-scale cylinder as prototypical curved object, we perform longitudinal and Hall voltage measurements while applying quantizing These are investigated function field strength angles. Most importantly, find that angle-dependent Shubnikov-de Hass oscillations superimposed with angle-independent features. Reproducing experimental observations, introduce network...
Quasi-one-dimensional magnets can host an ordered longitudinal spin-density wave state (LSDW) in magnetic field at low temperature, when correlations are strengthened by Ising anisotropies. In the S = 1/2 Heisenberg antiferromagnet YbAlO3 this happens via Ising-like interchain interactions. Here, we report first experimental observation of magnetization plateaux 1/5 and 1/3 saturation value thermal transport magnetostriction measurements YbAlO3. We present a phenomenological theory plateau...
We have studied electron spin resonance (ESR) absorption spectra for the nonmagnetically diluted strong-leg ladder magnet (${\mathrm{C}}_{7}{\mathrm{H}}_{10}{\mathrm{N})}_{2}{\mathrm{Cu}}_{(1\ensuremath{-}x)}{\mathrm{Zn}}_{x}{\mathrm{Br}}_{4}$ (abbreviated as DIMPY) down to 450 mK. Formation of clusters with nonzero net magnetization is confirmed; cluster-cluster interaction evidenced by concentration dependence ESR absorption. High-temperature spin-relaxation time was found increase...