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Related papers: Valley blockade and multielectron spin-valley Kond…

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We show that the mixing between spin and valley degrees of freedom in a silicon quantum bit (qubit) can be controlled by a static electric field acting on the valley splitting $\Delta$. Thanks to spin-orbit coupling, the qubit can be…

Mesoscale and Nanoscale Physics · Physics 2018-05-02 Léo Bourdet , Yann-Michel Niquet

We investigate the boundary phenomena that arise in a finite-size $XX$ spin chain interacting through an $XX$ interaction with a spin$-\frac{1}{2}$ impurity located at its edge. Upon Jordan-Wigner transformation, the model is described by a…

Strongly Correlated Electrons · Physics 2025-07-17 Pradip Kattel , Yicheng Tang , J. H. Pixley , Natan Andrei

The Hall conductivity $\sigma_{xy}$ of many condensed matter systems presents a step structure when a uniform perpendicular magnetic field is applied. We report the quantum Hall effect in buckled AB-bottom-top bilayer silicene and its…

Computational Physics · Physics 2019-10-23 Thi-Nga Do , Godfrey Gumbs , Po-Hsin Shih , Danhong Huang , Ming-Fa Lin

We study the Kondo effect in a CNT(left lead)-CNT(QD)-CNT(right lead) structure. Here CNT is a single-wall metallic carbon nanotube, for which 1) the valence and conduction bands of electrons with zero orbital angular momentum ($m=0$)…

Strongly Correlated Electrons · Physics 2014-05-14 Igor Kuzmenko , Yshai Avishai

We study the Kondo effect due to the nonmagnetic impurity, e.g., Zn, in high-T_c cuprates based on the spin-change separated state. In the optimal or overdoped case with the Kondo screening, the residual resistivity is dominated by the…

Condensed Matter · Physics 2016-08-31 Naoto Nagaosa , Patrick A. Lee

The out-of-equilibrium electron transport of carbon nanotube semiconducting quantum dot placed in a magnetic field is studied in the Kondo regime by means of the non-equilibrium Green functions. The equation of motion method is used. For…

Mesoscale and Nanoscale Physics · Physics 2009-01-27 D. Krychowski , S. Lipinski

The presence of non-degenerate valley states in silicon can drastically affect electron dynamics in silicon-based heterostructures, leading to electron spin relaxation and spin-valley coupling. In the context of solid-state spin qubits, it…

Mesoscale and Nanoscale Physics · Physics 2020-11-18 Nicholas E. Penthorn , Joshua S. Schoenfield , Lisa F. Edge , HongWen Jiang

A magnetic moment in a metal or in a quantum dot is, at low temperatures, screened by the conduction electrons through the mechanism of the Kondo effect. This gives rise to spin-spin correlations between the magnetic moment and the…

Strongly Correlated Electrons · Physics 2009-11-24 Andreas Holzner , Ian P. McCulloch , Ulrich Schollwöck , Jan von Delft , Fabian Heidrich-Meisner

Valley, the energy extrema in the electronic band structure at momentum space, is regarded as a new degree of freedom of electrons, in addition to charge and spin. The studies focused on valley degree of freedom now form an emerging field…

Materials Science · Physics 2020-02-13 He Hu , Wen-Yi Tong , Yu-Hao Shen , Xiangang Wan , Chun-Gang Duan

Research on Si quantum dot spin qubits is motivated by the long spin coherence times measured in Si, yet the orbital spectrum of Si dots is increased as a result of the valley degree of freedom. The valley degeneracy may be lifted by the…

Mesoscale and Nanoscale Physics · Physics 2015-05-18 Dimitrie Culcer , Lukasz Cywinski , Qiuzi Li , Xuedong Hu , S. Das Sarma

The valley splitting of 2D electrons in doubly-gated silicon-on-insulator quantum wells is studied by low temperature transport measurements under magnetic fields. At the buried thermal-oxide SiO$_{2}$ interface, the valley splitting…

Mesoscale and Nanoscale Physics · Physics 2025-09-03 Nathan Aubergier , Vincent T. Renard , Sylvain Barraud , Kei Takashina , Benjamin A. Piot

The observation of the Kondo effect in mesoscopic systems under bias$^{1,2}$ has opened a new chapter in the physics of the Kondo phenomenon. Various types of $dI/dV$, where $I$ and $V$ denote current and source-drain (s-d) bias,…

Mesoscale and Nanoscale Physics · Physics 2013-01-25 Jongbae Hong

We present a careful and thorough microscopic derivation of the Kondo Hamiltonian for single-molecule magnets (SMMs) transistors. When the molecule is strongly coupled to metallic leads, we show that by applying a transverse magnetic field…

Strongly Correlated Electrons · Physics 2009-11-13 Gabriel Gonzalez , Michael N. Leuenberger , Eduardo R. Mucciolo

The effect of a magnetic field on the spectral density of a $\rm{S=1/2}$ Kondo impurity is investigated at zero and finite temperatures by using Wilson's numerical renormalization group method. A splitting of the total spectral density is…

Strongly Correlated Electrons · Physics 2009-10-31 T. A. Costi

The Kondo effect emerges when a localized spin is screened by conduction electrons, giving rise to a strongly-correlated many-body ground state. In this work, we investigate this phenomenon in a GaAs/AlGaAs quantum dot, focusing on the…

The presence of valley states is a significant obstacle to realizing quantum information technologies in Silicon quantum dots, as leakage into alternate valley states can introduce errors into the computation. We use a perturbative…

Mesoscale and Nanoscale Physics · Physics 2022-01-25 Donovan Buterakos , Sankar Das Sarma

Silicon metal-oxide-semiconductor field effect transistors (MOSFETs) fabricated on a SIMOX (001) substrate, which is a kind of silicon on insulator (SOI) substrate, that is annealed at high temperature for a long time are known to exhibit…

Mesoscale and Nanoscale Physics · Physics 2024-07-08 Jinichiro Noborisaka , Toshiaki Hayashi , Akira Fujiwara , Katsuhiko Nishiguchi

The large, level-dependent g-factors in an InSb nanowire quantum dot allow for the occurrence of a variety of level crossings in the dot. While we observe the standard conductance enhancement in the Coulomb blockade region for aligned…

Mesoscale and Nanoscale Physics · Physics 2010-05-07 H. A. Nilsson , O. Karlström , M. Larsson , P. Caroff , J. N. Pedersen , L. Samuelson , A. Wacker , L. E. Wernersson , H. Q. Xu

We investigate theoretically the linear conductance of a two-level quantum dot as a function of the gate voltage and different strength of coupling to the external electronic system (the reservoir). Apart from the weak coupling regime,…

Mesoscale and Nanoscale Physics · Physics 2009-11-10 A. L. Chudnovskiy , S. E. Ulloa

Following the discovery of the Kondo effect the bulk transport and magnetic behavior of the dilute magnetic alloys have been successfully described. In the last fifteen years new directions have been developed as the study of the systems of…

Strongly Correlated Electrons · Physics 2020-04-22 O. Ujsaghy , A. Zawadowski