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Coulomb-enhanced dynamic localization and Bell state generation in coupled quantum dots: We investigate the dynamics of two interacting electrons in coupled quantum dots driven by an AC field. We find that the two electrons can be trapped in one of the dots by the AC field, in spite of the strong Coulomb repulsion. I...
cond-mat_mes-hall
Purcell effect at metal-insulator transitions: We investigate the spontaneous emission rate of a two-level quantum emitter next to a composite medium made of randomly distributed metallic inclusions embedded in a dielectric host matrix. In the near-field, the Purcell factor can be enhanced by two-orders of magnitude re...
cond-mat_mes-hall
Interlayer binding energy of graphite -- A direct experimental determination: Despite interlayer binding energy is one of the most important material properties for graphite, there is still lacking report on its direct experimental determination. In this paper, we present a novel experimental method to directly measu...
cond-mat_mes-hall
Observation of collapse of pseudospin order in bilayer quantum Hall ferromagnets: The Hartree-Fock paradigm of bilayer quantum Hall states with finite tunneling at filling factor $\nu$=1 has full pseudospin ferromagnetic order with all the electrons in the lowest symmetric Landau level. Inelastic light scattering mea...
cond-mat_mes-hall
Resonant plasmonic effects in periodic graphene antidot arrays: We show that a graphene sheet perforated with micro- or nano-size antidots have prominent absorption resonances in the microwave and terahertz regions. These resonances correspond to surface plasmons of a continuous sheet "perturbed" by a lattice. They are...
cond-mat_mes-hall
Floquet approach to bichromatically driven cavity optomechanical systems: We develop a Floquet approach to solve time-periodic quantum Langevin equations in steady state. We show that two-time correlation functions of system operators can be expanded in a Fourier series and that a generalized Wiener-Khinchin theorem re...
cond-mat_mes-hall
A-geometrical approach to Topological Insulators with defects: The study of the propagation of electrons with a varying spinor orientability is performed using the coordinate transformation method. Topological Insulators are characterized by an odd number of changes of the orientability in the Brillouin zone. For defec...
cond-mat_mes-hall
Dynamics of quantum cellular automata electron transition in triple quantum dots: The quantum cellular automata (QCA) effect is a transition in which multiple electron move coordinately by Coulomb interactions and observed in multiple quantum dots. This effect will be useful for realizing and improving quantum cellul...
cond-mat_mes-hall
Microwave Rectification at the Boundary between Two-Dimensional Electron Systems: Rectification of microwave radiation (20-40 GHz) by a line boundary between two two-dimensional metals on a silicon surface was observed and investigated at different temperatures, in-plane magnetic fields and microwave powers. The rect...
cond-mat_mes-hall
Quantum electrodynamic approach to the conductivity of gapped graphene: The electrical conductivity of graphene with a nonzero mass-gap parameter is investigated starting from the first principles of quantum electrodynamics in (2+1)-dimensional space-time at any temperature. The formalism of the polarization tensor def...
cond-mat_mes-hall
Non-invasive detection of charge-rearrangement in a quantum dot in high magnetic fields: We demonstrate electron redistribution caused by magnetic field on a single quantum dot measured by means of a quantum point contact as non-invasive detector. Our device which is fabricated by local anodic oxidation allows to con...
cond-mat_mes-hall
Monolithically integrated single quantum dots coupled to bowtie nanoantennas: Deterministically integrating semiconductor quantum emitters with plasmonic nano-devices paves the way towards chip-scale integrable, true nanoscale quantum photonics technologies. For this purpose, stable and bright semiconductor emitters ...
cond-mat_mes-hall
Emission and absorption asymmetry in the quantum noise of a Josephson junction: We measure current fluctuations of mesoscopic devices in the quantum regime, when the frequency is of the order of or higher than the applied voltage or temperature. Detection is designed to probe separately the absorption and emission co...
cond-mat_mes-hall
Bilayer WSe$_2$ as a natural platform for interlayer exciton condensates in the strong coupling limit: Exciton condensates (EC) are macroscopic coherent states arising from condensation of electron-hole pairs. Bilayer heterostructures, consisting of two-dimensional electron and hole layers separated by a tunnel barri...
cond-mat_mes-hall
Cavity-enhanced measurements of defect spins in silicon carbide: The identification of new solid-state defect qubit candidates in widely used semiconductors has the potential to enable the use of nanofabricated devices for enhanced qubit measurement and control operations. In particular, the recent discovery of optical...
cond-mat_mes-hall
Topological Hall signatures of magnetic hopfions: Magnetic hopfions are topologically protected three-dimensional solitons that are constituted by a tube which exhibits a topologically nontrivial spin texture in the cross-section profile and is closed to a torus. Here we show that the hopfion's locally uncompensated em...
cond-mat_mes-hall
Quasiparticle scattering off phase boundaries in epitaxial graphene: We investigate the electronic structure of terraces of single layer graphene (SLG) by scanning tunneling microscopy (STM) on samples grown by thermal decomposition of 6H-SiC(0001) crystals in ultra-high vacuum. We focus on the perturbations of the loc...
cond-mat_mes-hall
High-fidelity quantum memory utilizing inhomogeneous nuclear polarization in a quantum dot: We numerically investigate the encoding and retrieval processes for a quantum memory realized in a semiconductor quantum dot, by focusing on the effect of inhomogeneously polarized nuclear spins whose polarization depends on t...
cond-mat_mes-hall
Photon properties of single graphene nanoribbon microcavity laser: In this work, I propose a scheme about a single graphene nanoribbon (GNR) emitter in a microcavity, and focus on a fully-quantum-mechanical treatment model with the excitonic interaction included to investigate the photon properties and lasing action. W...
cond-mat_mes-hall
Spatial Confinement, Magnetic Localization and Their Interactions on Massless Dirac Fermions: It is of keen interest to researchers understanding different approaches to confine massless Dirac fermions in graphene, which is also a central problem in making electronic devices based on graphene. Here, we studied spatia...
cond-mat_mes-hall
Elastic strain field due to an inclusion of a polyhedral shape with a non-uniform lattice misfit: An analytical solution in a closed form is obtained for the three-dimensional elastic strain distribution in an unlimited medium containing an inclusion with a coordinate-dependent lattice mismatch (an eigenstrain). Quan...
cond-mat_mes-hall
Hot exciton relaxation in coupled ultra-thin CdTe/ZnTe quantum well structures: The photoluminescence (PL) and PL excitation (PLE) spectra of CdTe/ZnTe asymmetric double quantum well (QW) structures are studied on a series of samples containing two CdTe layers with nominal thicknesses of 2 and 4 monolayers (ML) in th...
cond-mat_mes-hall
Influence of Nuclear Quadrupole Moments on Electron Spin Coherence in Semiconductor Quantum Dots: We theoretically investigate the influence of the fluctuating Overhauser field on the spin of an electron confined to a quantum dot (QD). The fluctuations arise from nuclear angular momentum being exchanged between diffe...
cond-mat_mes-hall
Ultrafast Relaxation Dynamics of Photoexcited Dirac Fermion in The Three Dimensional Dirac Semimetal Cadmium Arsenide: Three dimensional (3D) Dirac semimetals which can be seen as 3D analogues of graphene have attracted enormous interests in research recently. In order to apply these ultrahigh-mobility materials in f...
cond-mat_mes-hall
Carbon Nanotube Thermal Transport: Ballistic to Diffusive: We propose to use l_0/(l_0+L) for the energy transmission covering both ballistic and diffusive regimes, where l_0 is mean free path and L is system length. This formula is applied to heat conduction in carbon nanotubes (CNTs). Calculations of thermal conductio...
cond-mat_mes-hall
Practical Guide to Quantum Phase Transitions in Quantum-Dot-Based Tunable Josephson Junctions: Quantum dots attached to BCS superconducting leads exhibit a $0-\pi$ impurity quantum phase transition, which can be experimentally controlled either by the gate voltage or by the superconducting phase difference. For the p...
cond-mat_mes-hall
Giant Magneto-Oscillations of Electric-Field-Induced Spin Polarization in 2DEG: We consider a disordered two-dimensional electron gas with spin-orbit coupling placed in a perpendicular magnetic field and calculate the magnitude and direction of the electric-field-induced spin polarization. We find that in strong magn...
cond-mat_mes-hall
Magnetic Response in Mesoscopic Rings and Moebius Strips: A Theoretical Study: We investigate magnetic response in mesoscopic rings and moebius strips penetrated by magnetic flux $\phi$. Based on a simple tight-binding framework all the calculations are performed numerically which describe persistent current and low-...
cond-mat_mes-hall
Shot noise in diffusive conductors: A quantitative analysis of electron-phonon interaction effects: Using the 'drift-diffusion-Langevin' equation, we have quantitatively analyzed the effects of electron energy relaxation via their interaction with phonons, generally in presence of electron-electron interaction, on sh...
cond-mat_mes-hall
Magnetic translations for a spatially periodic magnetic field: It is shown that in the case of free electron in a spatially periodic magnetic field the concept of magnetic translations operators is still valid and, moreover, these operators can be defined in the same way as for a Bloch electron in a uniform magnetic fi...
cond-mat_mes-hall
PT Symmetric Floquet Topological Phase: In this paper, we study the existence of Floquet topological insulators for PT symmetric non-Hermitian Hamiltonians. We consider an array of waveguide in 1D with periodically changing non-Hermitian potential and predict the existence of Floquet topological insulators in the syste...
cond-mat_mes-hall
Enhanced longevity of the spin helix in low-symmetry quantum wells: In a semiconductor, collective excitations of spin textures usually decay rather fast due to D'yakonov-Perel' spin relaxation. The latter arises from spin-orbit coupling, which induces wave-vector-dependent spin rotations that, in conjunction with rand...
cond-mat_mes-hall
Optimized Tersoff and Brenner empirical potential parameters for lattice dynamics and phonon thermal transport in carbon nanotubes and graphene: We have examined the commonly used Tersoff and Brenner empirical interatomic potentials in the context of the phonon dispersions in graphene. We have found a parameter set f...
cond-mat_mes-hall
Magnetic Splitting of the Zero Bias Peak in a Quantum Point Contact with a Variable Aspect Ratio: We report a zero-bias peak in the differential conductance of a Quantum Point Contact (QPC), which splits in an external magnetic field. The peak is observed over a range of device conductance values starting significant...
cond-mat_mes-hall
Transport Study of Charge Carrier Scattering in Monolayer WSe$_2$: Employing flux-grown single crystal WSe$_2$, we report charge carrier scattering behaviors measured in $h$-BN encapsulated monolayer field effect transistors. We perform quantum transport measurements across various hole densities and temperatures and o...
cond-mat_mes-hall
Magnetically induced oscillations of the spin polarization in the Datta-Das geometry: The control of intrinsic magnetic degrees of freedom is very important as it offers a practical means to manipulate and probe electron spin transport. Tunable spin-orbit effect in quantum wires can in principle serve as a means to a...
cond-mat_mes-hall
Vacancy-induced localized modes and impurity band formation in the Haldane model: a quantum dot analogy: In this study, the Haldane model's edge states are utilized to illustrate that a zero-energy localized state forms around a single vacancy in the model. In order to complete this task, the conventional unit cell a...
cond-mat_mes-hall
Cryogenic spin Seebeck effect: We present a theory of the non-linearities of the spin Seebeck effect (SSE) in a ferromagnetic nanowire at cryogenic temperatures. We adopt a microscopic quantum noise model based on a collection of two-level systems. At certain positions of Pt detectors to the wire, the transverse SSE ch...
cond-mat_mes-hall
Tunable ferroelectricity in hBN intercalated twisted double-layer graphene: Van der Waals (vdW) assembly of two-dimensional materials has been long recognized as a powerful tool to create unique systems with properties that cannot be found in natural compounds. However, among the variety of vdW heterostructures and t...
cond-mat_mes-hall
On the Implications of Discrete Symmetries for the Beta Function of Quantum Hall Systems: We argue that the large discrete symmetry group of quantum Hall systems is insufficient in itself to determine the complete beta function for the scaling of the conductivities, $\sigma_{xx}$ and $\sigma_{xy}$. We illustrate this...
cond-mat_mes-hall
Large quantum nonlinear dynamic susceptibility of single-molecule magnets: The nonlinear dynamical response of Mn$_{12}$ single-molecule magnets is experimentally found to be very large, quite insensitive to the spin-lattice coupling constant, and displaying peaks reversed with respect to classical superparamagnets. ...
cond-mat_mes-hall
The electronic properties of doped single walled carbon nanotubes and carbon nanotube sensors: We present ab initio calculations on the band structure and density of states of single wall semiconducting carbon nanotubes with high degrees (up to 25%) of B, Si and N substitution. The doping process consists of two phas...
cond-mat_mes-hall
Trigonal distortion of topologically confined channels in bilayer Graphene: In this work we show that the trigonal warping of the electronic bands in bilayer graphene dramatically modifies the behavior of the one-dimensional modes topologically confined due to an inhomogeneous bias that changes sign across a channel....
cond-mat_mes-hall
Oligothiophene nano-rings as electron resonators for whispering gallery modes: Structural and electronic properties of oligothiophene nano-wires and rings synthesized on a Au(111) surface are investigated by scanning tunneling microscopy. The spectroscopic data of the linear and cyclic oligomers show remarkable diffe...
cond-mat_mes-hall
Dynamical separation of bulk and edge transport in HgTe-based 2D topological insulators: Topological effects in edge states are clearly visible on short lengths only, thus largely impeding their studies. On larger distances, one may be able to dynamically enhance topological signatures by exploiting the high mobility...
cond-mat_mes-hall
Magneto-elastic universal logic gate: A non-volatile, error-resilient Boolean logic gate with ultra-low energy-delay product: A long-standing goal of computer technology is to process and store digital information with the same device in order to implement new architectures. One way to accomplish this is to use nanom...
cond-mat_mes-hall
Superfluidity of Dipolar Excitons in a Black Phosphorene Double Layer: We study the formation of dipolar excitons and their superfluidity in a black phosphorene double layer. The analytical expressions for the single dipolar exciton energy spectrum and wave function are obtained. It is predicted that a weakly interacti...
cond-mat_mes-hall
Optical generation and detection of pure valley current in monolayer transition metal dichalcogenides: We propose a practical scheme to generate a pure valley current in monolayer transition metal dichalcogenides by one-photon absorption of linearly polarized light. We show that the pure valley current can be detecte...
cond-mat_mes-hall
Quantum oscillations observed in graphene at microwave frequencies: We have measured the microwave conductance of mechanically exfoliated graphene at frequencies up to 8.5 GHz. The conductance at 4.2 K exhibits quantum oscillations, and is independent of the frequency.
cond-mat_mes-hall
Time Reversal Invariant Topologically Insulating Circuits: From studies of exotic quantum many-body phenomena to applications in spintronics and quantum information processing, topological materials are poised to revolutionize the condensed matter frontier and the landscape of modern materials science. Accordingly, the...
cond-mat_mes-hall
Domain wall motion at low current density in a synthetic antiferromagnet nanowire: The current-driven motion of magnetic domain walls (DWs) is the working principle of magnetic racetrack memories. In this type of spintronic technology, high current densities are used to propel DW motion in magnetic nanowires, causing...
cond-mat_mes-hall
Persistent current of correlated electrons in mesoscopic ring with impurity: The persistent current of correlated electrons in a continuous one-dimensional ring with a single scatterer is calculated by solving the many-body Schrodinger equation for several tens of electrons interacting via the electron-electron (e-e)...
cond-mat_mes-hall
Current-induced forces in mesoscopic systems: a scattering matrix approach: Nanoelectromechanical systems are characterized by an intimate connection between electronic and mechanical degrees of freedom. Due to the nanoscopic scale, current flowing through the system noticeably impacts the vibrational dynamics of the...
cond-mat_mes-hall
Microwave Experiments Simulating Quantum Search and Directed Transport in Artificial Graphene: A series of quantum search algorithms have been proposed recently providing an algebraic speedup compared to classical search algorithms from $N$ to $\sqrt{N}$, where $N$ is the number of items in the search space. In parti...
cond-mat_mes-hall
In-plane gate single-electron transistor in Ga[Al]As fabricated by scanning probe lithography: A single-electron transistor has been realized in a Ga[Al]As heterostructure by oxidizing lines in the GaAs cap layer with an atomic force microscope. The oxide lines define the boundaries of the quantum dot, the in-plane g...
cond-mat_mes-hall
Plasmons in realistic graphene/hexagonal boron nitride moiré patterns: Van der Waals heterostructures employing graphene and hexagonal boron nitride (hBN) crystals have emerged as a promising platform for plasmonics thanks to the tunability of their collective modes with carrier density and record values for plasmonics...
cond-mat_mes-hall
Non-equilibrium fractional quantum Hall states visualized by optically detected MRI: Using photoluminescence microscopy enhanced by MRI, we visualize in real space both electron and nuclear polarization occurring in non-equilibrium FQH liquids. We observe stripe-like regions comprising FQH excited states which discre...
cond-mat_mes-hall
Directional emission of a deterministically fabricated quantum dot - Bragg reflection multi-mode waveguide system: We report on the experimental study and numerical analysis of chiral light-matter coupling in deterministically fabricated quantum dot (QD) waveguide structures. We apply in-situ electron beam lithograph...
cond-mat_mes-hall
Strong parametric coupling between two ultra-coherent membrane modes: We demonstrate parametric coupling between two modes of a silicon nitride membrane. We achieve the coupling by applying an oscillating voltage to a sharp metal tip that approaches the membrane surface to within a few 100 nm. When the voltage oscillat...
cond-mat_mes-hall
Room-temperature coherent optical manipulation of single-hole spins in solution-grown perovskite quantum dots: Manipulation of solid-state spin coherence is an important paradigm for quantum information processing. Current systems either operate at very low temperatures or are difficult to scale-up. Developing low-co...
cond-mat_mes-hall
Micromagnetic Simulation of Amorphous Ferrimagnetic TbFeCo Films with Exchange Coupled Nanophases: Amorphous ferrimagnetic TbFeCo thin films are found to exhibit exchange bias effect near the compensation temperature by magnetic hysteresis loop measurement. The observed exchange anisotropy is believed to originate fr...
cond-mat_mes-hall
Photogalvanic effect in Weyl semimetals: We theoretically study the impact of impurities on the photogalvanic effect (PGE) in Weyl semimetals with weakly tilted Weyl cones. Our calculations are based on a two-nodes model with an inversion symmetry breaking offset and we employ a kinetic equation approach in which both ...
cond-mat_mes-hall
Topological Hofstadter Insulators in a Two-Dimensional Quasicrystal: We investigate the properties of a two-dimensional quasicrystal in the presence of a uniform magnetic field. In this configuration, the density of states (DOS) displays a Hofstadter butterfly-like structure when it is represented as a function of the ...
cond-mat_mes-hall
True amplification of spin waves in magnonic nano-waveguides: Magnonic nano-devices exploit magnons -- quanta of spin waves -- to transmit and process information within a single integrated platform that has the potential to outperform traditional semiconductor-based electronics for low power applications. The main mis...
cond-mat_mes-hall
Pair-wise decoherence in coupled spin qubit networks: Experiments involving phase coherent dynamics of networks of spins, such as echo experiments, will only work if decoherence can be suppressed. We show here, by analyzing the particular example of a crystalline network of Fe8 molecules, that most decoherence typicall...
cond-mat_mes-hall
Hot electrons in a tunnel structure based on metal nanoclusters: We study the effect of temperature on the tunnel current in a structure based on gold clusters taking into consideration their discrete electronic spectra. We suggest that an overheating of electron subsystem leads to the disappearance of a current gap an...
cond-mat_mes-hall
Kondo Effect in a Many-Electron Quantum Ring: The Kondo effect is investigated in a many-electron quantum ring as a function of magnetic field. For fields applied perpendicular to the plane of the ring a modulation of the Kondo effect with the Aharonov-Bohm period is observed. This effect is discussed in terms of the e...
cond-mat_mes-hall
Spin-Hall Effect in A Symmetric Quantum Wells by A Random Rashba Field: Changes dopant ion concentrations in the sides of a symmetric quantum well are known to create a random Rashba-type spin-orbit coupling. Here we demonstrate that, as a consequence, a finite size spin-Hall effect is also present. Our numerical algor...
cond-mat_mes-hall
Coulomb drag in graphene near the Dirac point: We study Coulomb drag in double-layer graphene near the Dirac point. A particular emphasis is put on the case of clean graphene, with transport properties dominated by the electron-electron interaction. Using the quantum kinetic equation framework, we show that the drag be...
cond-mat_mes-hall
Hot electron cooling by acoustic phonons in graphene: We have investigated the energy loss of hot electrons in metallic graphene by means of GHz noise thermometry at liquid helium temperature. We observe the electronic temperature T / V at low bias in agreement with the heat diffusion to the leads described by the Wied...
cond-mat_mes-hall
Micromagnetic view on ultrafast magnon generation by femtosecond spin current pulses: In this Article we discuss a micromagnetic modelling approach to describe the ultrafast spin-transfer torque excitation of coherent and incoherent magnons on the nanoscale. Implementing the action of a femtosecond spin current pulse...
cond-mat_mes-hall
"Smoking gun" signatures of topological milestones in trivial materials by measurement fine-tuning and data postselection: Exploring the topology of electronic bands is a way to realize new states of matter with possible implications for information technology. Because bands cannot always be observed directly, a cent...
cond-mat_mes-hall
Liquid exfoliation of solvent-stabilised black phosphorus: applications beyond electronics: Few layer black phosphorus is a new two-dimensional material which is of great interest for applications, mainly in electronics. However, its lack of stability severely limits our ability to synthesise and process this materia...
cond-mat_mes-hall
Diffusion of photo-excited holes in viscous electron fluid: The diffusion of photo-generated holes is studied in a high-mobility mesoscopic GaAs\ channel where electrons exhibit hydrodynamic properties. It is shown that the injection of holes into such an electron system leads to the formation of a hydrodynamic three-c...
cond-mat_mes-hall
Temperature effect in the conductance of hydrogen molecule: We present a many-body calculation for the conductance of a conducting bridge of a simple hydrogen molecule between $Pt$ electrodes.The experimental results showed that the conductance $G=dI/dV$ has the maximum value near the quantum unit $G_{0}=2e^{2}/h$. T...
cond-mat_mes-hall
Current and Shot Noise in a Quantum Dot Coupled to Ferromagnetic Leads in the Large U Limit: Using the Keldysh nonequilibrium Green function technique, we study the current and shot noise spectroscopy of a single interacting quantum dot coupled to two ferromagnetic leads with different polarizations. The polarization...
cond-mat_mes-hall
Electron spin resonance on a 2-dimensional electron gas in a single AlAs quantum well: Direct electron spin resonance (ESR) on a high mobility two dimensional electron gas in a single AlAs quantum well reveals an electronic $g$-factor of 1.991 at 9.35 GHz and 1.989 at 34 GHz with a minimum linewidth of 7 Gauss. The E...
cond-mat_mes-hall
Near-Field Radiative Heat Transfer between Drift-biased Graphene through Nonreciprocal Surface Plasmons: In this Rapid Communication, we theoretically demonstrate that near-field radiative heat transfer (NFRHT) can be modulated and enhanced by a new energy transmission mode of evanescent wave, i.e. the nonreciprocal ...
cond-mat_mes-hall
What do noise measurements reveal about fractional charge in FQH liquids?: We present a calculation of noise in the tunneling current through junctions between two two-dimensional electron gases (2DEG) in inequivalent Laughlin fractional quantum Hall (FQH) states, as a function of voltage and temperature. We discuss ...
cond-mat_mes-hall
Sub-to-super-Poissonian photon statistics in cathodoluminescence of color center ensembles in isolated diamond crystals: Impurity-vacancy centers in diamond offer a new class of robust photon sources with versatile quantum properties. While individual color centers commonly act as single-photon sources, their ensembl...
cond-mat_mes-hall
Field-induced dissociation of two-dimensional excitons in transition-metal dichalcogenides: Generation of photocurrents in semiconducting materials requires dissociation of excitons into free charge carriers. While thermal agitation is sufficient to induce dissociation in most bulk materials, an additional push is re...
cond-mat_mes-hall
Non-stationary effects in the coupled quantum dots influenced by the electron-phonon interaction: We analyzed time evolution of the localized charge in the system of two interacting single level quantum dots (QDs) coupled with the continuous spectrum states in the presence of electron-phonon interaction. We demonst...
cond-mat_mes-hall
Finite-size scaling effect on Néel temperature of antiferromagnetic Cr$_2$O$_3$-(0001) films in an exchange-coupled heterostructure: The scaling of antiferromagnetic ordering temperature of corundum-type chromia films have been investigated. N\'eel temperature $T_N$ was determined from the effect of perpendicular exc...
cond-mat_mes-hall
Spin-orbit fields in asymmetric (001) quantum wells: We measure simultaneously the in-plane electron g-factor and spin relaxation rate in a series of undoped inversion-asymmetric (001)-oriented GaAs/AlGaAs quantum wells by spin-quantum beat spectroscopy. In combination the two quantities reveal the absolute values of b...
cond-mat_mes-hall
Dirac-point engineering and topological phase transitions in honeycomb optical lattices: We study the electronic structure and the phase diagram of non-interacting fermions confined to hexagonal optical lattices. In the first part, we compare the properties of Dirac points arising in the eigenspectrum of either honey...
cond-mat_mes-hall
Shot noise of series quantum point contacts intercalating chaotic cavities: Shot noise of series quantum point contacts forming a sequence of cavities in a two dimensional electron gas are studied theoretically and experimentally. Noise in such a structure originates from local scattering at the point contacts as wel...
cond-mat_mes-hall
Giga-Hertz quantized charge pumping in bottom gate defined InAs nanowire quantum dots: Semiconducting nanowires (NWs) are a versatile, highly tunable material platform at the heart of many new developments in nanoscale and quantum physics. Here, we demonstrate charge pumping, i.e., the controlled transport of individ...
cond-mat_mes-hall
Analytical description of the 1s exciton linewidth temperature-dependence in transition metal dichalcogenides: We obtain an analytical expression for the linewidth of the 1s-exciton as a function of temperature in transition metal dichalcogenides. The total linewidth, as function of temperature, is dominated by three...
cond-mat_mes-hall
Topological Number of Edge States: We show that the edge states of the four-dimensional class A system can have topological charges, which are characterized by Abelian/non-Abelian monopoles. The edge topological charges are a new feature of relations among theories with different dimensions. From this novel viewpoint, ...
cond-mat_mes-hall
Controllable Spin-Transfer Torque on an Antiferromagnet in a Dual Spin-Valve: We consider current-induced spin-transfer torque on an antiferromagnet in a dual spin-valve setup. It is demonstrated that a net magnetization may be induced in the AFM by partially or completely aligning the sublattice magnetizations via a...
cond-mat_mes-hall
Signatures of spin-orbit coupling in scanning gate conductance images of electron flow from quantum point contacts: Electron flow through a quantum point contact in presence of spin-orbit coupling is investigated theoretically in the context of the scanning gate microscopy (SGM) conductance mapping. Although in the a...
cond-mat_mes-hall
Probing the potential landscape inside a two-dimensional electron-gas: We report direct observations of the scattering potentials in a two-dimensional electron-gas using electron-beam diffaction-experiments. The diffracting objects are local density-fluctuations caused by the spatial and charge-state distribution of th...
cond-mat_mes-hall
Mechanism for self-formation of periodic structures on a plastic polymer surface using a nanosecond and femtosecond laser pulses: The high UV laser dose at 193 nm induces grooves on poly allyl diglycol carbonate PADC (CR39) at normal irradiation. The spatial period exhibits to be nearly invariant for azimuth and pola...
cond-mat_mes-hall
Control of Plasmons in Topological Insulators via Local Perturbations: We use a fully quantum mechanical approach to demonstrate control of plasmonic excitations in prototype models of topological insulators by molecule-scale perturbations. Strongly localized surface plasmons are present in the host systems, arising fr...
cond-mat_mes-hall
One-Dimensional Luttinger Liquids in a Two-Dimensional Moiré Lattice: The Luttinger liquid (LL) model of one-dimensional (1D) electronic systems provides a powerful tool for understanding strongly correlated physics including phenomena such as spin-charge separation. Substantial theoretical efforts have attempted to ex...
cond-mat_mes-hall
Anomalous Nernst effect and field-induced Lifshitz transition in Weyl semimetals TaP and TaAs: The discovery of Weyl fermions in transition metal monoarsenides/phosphides without inversion symmetry represents an exceptional breakthrough in modern condensed matter physics. However, exploring the inherent nature of the...
cond-mat_mes-hall
Tunnel magnetoresistance and temperature related effects in magnetic tunnel junctions with embedded nanoparticles: Temperature dependence of the tunnel magnetoresistance (TMR) was calculated in range of the quantum-ballistic model in the magnetic tunnel junctions (MTJs) with embedded nanoparticles (NPs). The electron...
cond-mat_mes-hall
Compensation of the Kondo effect in quantum dots coupled to ferromagnetic leads within equation of motion approach: We propose a new approximation scheme within equation of motion approach (EOM) to spin polarized transport through a quantum dot coupled to ferromagnetic leads. It has some advantages over a widely used...
cond-mat_mes-hall
Semiconductor quantum well irradiated by a two-mode electromagnetic field as a terahertz emitter: We study theoretically the nonlinear optical properties of a semiconductor quantum well (QW) irradiated by a two-mode electromagnetic wave consisting of a strong resonant dressing field and a weak off-resonant driving fi...
cond-mat_mes-hall
Mapping Spin Interactions from Conductance Peak Splitting in Coulomb Blockade: We investigate the transport properties of a quantum dot coupled to leads interacting with a multi-spin system using the generalized master equation within the Coulomb blockade regime. We find that if two states for each scattering region ...
cond-mat_mes-hall