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Related papers: Local moment formation in quantum point contacts

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A quantum point contact (QPC) is a very basic nano-electronic device: a short and narrow transport channel between two electron reservoirs. In clean channels electron transport is ballistic and the conductance $G$ is then quantised as a…

Spin-entanglement of two electrons occupying two spatial regions -- domains -- is expressed in a compact form in terms of spin-spin correlation functions. The power of the formalism is demonstrated on several examples ranging from…

Mesoscale and Nanoscale Physics · Physics 2009-04-10 A. Ramsak , J. Mravlje , T. Rejec

A quantum point contact (QPC), a narrow region separating two wider electron reservoirs, is the standard building block of sub-micron devices, such as quantum dots - small boxes of electrons, and qubits - the proposed basic elements of…

Mesoscale and Nanoscale Physics · Physics 2009-11-11 Tomaz Rejec , Yigal Meir

The continuous quantum phase transition and the nature of quantum critical point (QCP) in a modified Kondo lattice model with Ising anisotropic exchange interactions is studied within the density-matrix renormalization group algorithm. We…

Strongly Correlated Electrons · Physics 2018-06-20 W. Zhu , Jian-xin Zhu

We investigate the spin-dependent transport properties of quantum-dot based structures where Kondo correlations dominate the electronic dynamics. The coupling to ferromagnetic leads with parallel magnetizations is known to give rise to…

Mesoscale and Nanoscale Physics · Physics 2009-11-11 David Sanchez , Rosa Lopez , Mahn-Soo Choi

Charge Kondo circuits consist of metallic islands connected by single-mode quantum point contacts (QPCs). The island's charging energy makes these circuits tunable quantum simulators of various strongly interacting models. Here we propose a…

Mesoscale and Nanoscale Physics · Physics 2025-12-01 Zhanyu Ma , Cheolhee Han , F. Pierre , Eran Sela

We study the Kondo effect in the electron transport through a quantum dot coupled to ferromagnetic leads, using a real-time diagrammatic technique which provides a systematic description of the nonequilibrium dynamics of a system with…

Mesoscale and Nanoscale Physics · Physics 2007-05-23 Yasuhiro Utsumi , Jan Martinek , Gerd Schön , Hiroshi Imamura , Sadamichi Maekawa

We review the quantum interference effects in a system of interacting electrons confined to a quantum dot. The review starts with a description of an isolated quantum dot. We discuss the status of the Random Matrix theory (RMT) of the…

Mesoscale and Nanoscale Physics · Physics 2009-11-07 I. L. Aleiner , P. W. Brouwer , L. I. Glazman

The phenomenology of the "0.7 anomaly" in quantum point contacts is fully explained in terms of a quasi-localized state, which forms as the point contact opens up. Detailed numerical calculations within spin-density functional theory indeed…

Mesoscale and Nanoscale Physics · Physics 2009-11-13 Yigal Meir

We identify the precise hallmarks of the local magnetic moment formation and its Kondo screening in the frequency structure of the generalized charge susceptibility. The sharpness of our identification even pinpoints an alternative…

Strongly Correlated Electrons · Physics 2021-02-08 Patrick Chalupa , Thomas Schäfer , Matthias Reitner , Daniel Springer , Sabine Andergassen , Alessandro Toschi

We derive here a stability condition for a local moment in the presence of an interacting sea of conduction electrons. The conduction electrons are modeled as a Luttinger liquid in which chirality and spin are coupled. We show that an…

Condensed Matter · Physics 2009-10-28 Philip Phillips , Nancy Sandler

Weak spin-orbit coupling produces very limited current induced spin accumulation in semiconductor nanostructures. We demonstrate a possibility to increase parametrically the spin polarization using the Kondo effect. As a model object we…

Mesoscale and Nanoscale Physics · Physics 2023-07-26 V. N. Mantsevich , D. S. Smirnov

We study the out of equilibrium steady state properties of the Bose-Fermi-Kondo model, describing a local magnetic moment coupled to two ferromagnetic leads that support bosonic (magnons) and fermionic (Stoner continuum electrons) low…

Strongly Correlated Electrons · Physics 2015-06-15 Pedro Ribeiro , Qimiao Si , Stefan Kirchner

In this paper the dominant effect of electron inertia on the dynamics of localized density excitations is studied in a quantum plasma in the presence of electron spin effects. Using the quantum magnetohydrodynamics (QMHD) model including…

Plasma Physics · Physics 2015-05-30 M. Akbari-Moghanjoughi

We have developed a novel technique for detection of spin polarization with a quantum dot weakly coupled to the objective device. The disturbance to the object in this technique is very small since the detection is performed through…

Mesoscale and Nanoscale Physics · Physics 2016-12-21 Sunwoo Kim , Yoshiaki Hashimoto , Taketomo Nakamura , Shingo Katsumoto

We study formation of local magnetic moments in strongly correlated Hubbard model within dynamical mean field theory and associate peculiarities of temperature dependence of local charge $\chi_c$ and spin $\chi_s$ susceptibilities with…

Strongly Correlated Electrons · Physics 2022-03-01 T. B. Mazitov , A. A. Katanin

We show that spatially local, yet low-energy, fluctuations can play an essential role in the physics of strongly correlated electron systems tuned to a quantum critical point. A detailed microscopic analysis of the Kondo lattice model is…

Strongly Correlated Electrons · Physics 2009-11-07 Qimiao Si , Silvio Rabello , Kevin Ingersent , Lleweilun Smith

Perturbative scaling is applied to the Anderson model for a localized level coupled to a Fermi system in which the density of states varies like $|E|^r$ near the Fermi energy ($E=0$). This model with $r=1$ or $2$ may describe magnetic…

Condensed Matter · Physics 2009-09-25 Carlos Gonzalez-Buxton , Kevin Ingersent

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. In…

Mesoscale and Nanoscale Physics · Physics 2009-11-07 Ping Zhang , Qi-Kun Xue , Xian-Geng Zhao , X. C. Xie

The appearance of unconventional superconductivity near heavy-fermion quantum critical points (QCPs) motivates investigation of pairing correlations close to a ``beyond Landau'' Kondo-destruction QCP. We focus on a two-Anderson-impurity…

Strongly Correlated Electrons · Physics 2020-02-25 Ang Cai , J. H. Pixley , Kevin Ingersent , Qimiao Si