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Related papers: Fractional charge oscillations in quantum spin Hal…

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We use density-functional methods to study the effects of an external magnetic field on two-dimensional quantum dots with a rectangular hard-wall confining potential. The increasing magnetic field leads to spin polarization and formation of…

Strongly Correlated Electrons · Physics 2009-11-10 E. Räsänen , A. Harju , M. J. Puska , R. M. Nieminen

This work presents theoretical demonstration of a carrier trap unit formed by dual topological insulator constrictions (TIC) on the HgTe/CdTe quantum well (QW) with inverted band structures. The sample of HgTe/CdTe QW is patterned into a…

Mesoscale and Nanoscale Physics · Physics 2016-08-24 L. Z. Lin , Zhenhua Wu

Fractionalization is a phenomenon where an elementary excitation partitions into several pieces. This picture explains non-trivial transport through a junction of one-dimensional edge channels defined by topologically distinct quantum Hall…

Mesoscale and Nanoscale Physics · Physics 2021-01-27 Chaojing Lin , Masayuki Hashisaka , Takafumi Akiho , Koji Muraki , Toshimasa Fujisawa

Hyperfine coupling of electron spins to nuclear spins is studied for a GaAs-based double quantum dot in the spin blockade regime where the electron conduction is mostly blocked by Pauli effect unless the electron spin state in the double…

Mesoscale and Nanoscale Physics · Physics 2009-11-10 Keiji Ono , Seigo Tarucha

Understanding the nature of confinement, as well as its relation with the spontaneous breaking of chiral symmetry, remains one of the long-standing questions in high-energy physics. The difficulty of this task stems from the limitations of…

We consider a Dice model with Dirac cones intersected by a topologically flat band at the charge neutrality point and analyze the inelastic scattering of massless pseudospin-1 particles on a circular, gate-defined, oscillating barrier.…

Mesoscale and Nanoscale Physics · Physics 2020-04-22 Alexander Filusch , Christian Wurl , Holger Fehske

We study the magneto-conductance of a $1.4~\mathrm{\mu m}$-wide quantum dot in the fractional quantum Hall regime. For a filling factor $\approx 2/3$ and $\gtrsim 1/3$ in the quantum dot the observed Coulomb resonances show a periodic…

Two dimensional electron systems exhibiting the fractional quantum Hall effects are characterized by a quantized Hall conductance and a dissipationless bulk. The transport in these systems occurs only at the edges where gapless excitations…

Mesoscale and Nanoscale Physics · Physics 2009-11-10 Yogesh N. Joglekar , Hoang K. Nguyen , Ganpathy Murthy

The Kondo lattice model of spin-1/2 local moments coupled to the conduction electrons at half-filling is studied for its orbital response to magnetic field on bipartite lattices. Through an effective charge dynamics, in a canonical…

Strongly Correlated Electrons · Physics 2017-08-17 Panch Ram , Brijesh Kumar

Due to presence of magnetic field gradient needed for coherent spin control, dephasing of single-electron spin qubits in silicon quantum dots is often dominated by $1/f$ charge noise. We investigate theoretically fluctuations of ground…

Mesoscale and Nanoscale Physics · Physics 2024-08-09 Marcin Kępa , Niels Focke , Łukasz Cywiński , Jan. A. Krzywda

The charge of fractionally charged quasiparticles, proposed by Laughlin to explain the fractional quantum Hall effect (FQHE), was recently verified by measurements. Charge q=e/3 and e/5 (e is the electron charge), at filling factors nu=1/3…

Mesoscale and Nanoscale Physics · Physics 2009-11-10 Y. C. Chung , M. Heiblum , V. Umansky

Within an effective Dirac-Weyl theory we solve the scattering problem for massless chiral fermions impinging on a cylindrical time-dependent potential barrier. The set-up we consider can be used to model the electron propagation in a…

Mesoscale and Nanoscale Physics · Physics 2015-06-23 C. Schulz , R. L. Heinisch , H. Fehske

We consider quantum spin Hall effect in an anisotropic strip of stripes and address both integer and fractional filling factors. The first model is based on a gradient of spin-orbit interaction in the direction perpendicular to the stripes.…

Mesoscale and Nanoscale Physics · Physics 2014-10-01 Jelena Klinovaja , Yaroslav Tserkovnyak

We use Dirac quantization of flux to study fractional charges and axion angles \theta in interacting topological insulators with gapless surface modes protected by time-reversal symmetry. In interacting topological insulators, there are two…

Strongly Correlated Electrons · Physics 2010-10-12 K. -S. Park , H. Han

A quantum theory of the spin-dependent scattering of semiconductor electrons by a Schottky barrier at an interface with a ferromagnet is presented. The reflection of unpolarized non-equilibrium carriers produces spontaneous…

Mesoscale and Nanoscale Physics · Physics 2007-05-23 J. P. McGuire , C. Ciuti , L. J. Sham

Remarkable nonlinearities in the differential tunneling conductance between fractional quantum Hall edge states at a constriction are observed in the weak-backscattering regime. In the $\nu $ = 1/3 state a peak develops as temperature is…

Mesoscale and Nanoscale Physics · Physics 2009-11-07 Stefano Roddaro , Vittorio Pellegrini , Fabio Beltram , Giorgio Biasiol , Lucia Sorba , Roberto Raimondi , Giovanni Vignale

We study the resonant tunneling of quasiparticles through an impurity between the edges of a Fractional Quantum Hall sample. We show that the one-particle momentum distribution of fractionally charged edge quasiparticles has a quasi-Fermi…

Condensed Matter · Physics 2009-10-22 V. L. Pokrovsky , L. P. Pryadko

We report the observation of fractional shifts in the experimental stability diagrams of PbTe nanowire quantum dots. Although this behavior may appear to suggest fractional charge transport, akin to that reported in the fractional quantum…

Mesoscale and Nanoscale Physics · Physics 2025-04-08 Seth Byard , Maksim Gomanko , Sergey M. Frolov

We study the effect of charge discreteness in a quantum mesoscopic ring wih inductance L. The ring is pierced by a time depending external magnetic field. When the external magnetic flux varies uniformly, the current induced in the ring…

Mesoscale and Nanoscale Physics · Physics 2007-05-23 J. C. Flores , E. Lazo

We show that a quantum dot in the fractional Hall regime exhibits mesoscopic magnetic oscillations with a period which is a multiple of the period for free electrons. Our calculations are performed for parabolic quantum dots with hard-core…

Condensed Matter · Physics 2009-10-22 A. H. MacDonald , M. D. Johnson