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Related papers: Local moment formation in quantum point contacts

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It has been argued that the 0.7 anomaly in quantum point contacts (QPCs) is due to an enhanced density of states at the top of the QPC-barrier (van Hove ridge), which strongly enhances the effects of interactions. Here, we analyze their…

Mesoscale and Nanoscale Physics · Physics 2017-11-15 Dennis H. Schimmel , Benedikt Bruognolo , Jan von Delft

A new type of blockade effect - spin-orbit blockade (SOB) - is found in the conduction of a quantum dot (QD) made of a material with spin-orbit interaction. The blockade arises from spin-filtering effect in a quantum point contact (QPC),…

Mesoscale and Nanoscale Physics · Physics 2012-04-25 Sunwoo Kim , Yoshiaki Hashimoto , Yasuhiro Iye , Shingo Katsumoto

The current noise in a quantum dot coupled to two leads is investigated in the Kondo regime with and without the influence of magnetic fields by employing a finite-$U$ slave-boson mean field theory to calculate the current-current…

Mesoscale and Nanoscale Physics · Physics 2009-11-07 Bing Dong , X. L. Lei

We consider the steady-state thermoelectric transport through a vibrating molecular quantum dot that is contacted to macroscopic leads. For moderate electron-phonon interaction strength and comparable electronic and phononic timescales, we…

Mesoscale and Nanoscale Physics · Physics 2015-06-18 T. Koch , J. Loos , H. Fehske

We investigate the real-time current response of strongly-correlated quantum dot systems under sinusoidal driving voltages. By means of an accurate hierarchical equations of motion approach, we demonstrate the presence of prominent memory…

Strongly Correlated Electrons · Physics 2015-06-15 Xiao Zheng , YiJing Yan , Massimiliano Di Ventra

We argue that Coulomb blockade phenomena are a useful probe of the cross-over to strong correlation in quantum dots. Through calculations at low density using variational and diffusion quantum Monte Carlo (up to r_s ~ 55), we find that the…

Mesoscale and Nanoscale Physics · Physics 2009-08-11 A. D. Guclu , A. Ghosal , C. J. Umrigar , H. U. Baranger

We develop a local moment approach to static properties of the symmetric Anderson model in the presence of a magnetic field, focussing in particular on the strong coupling Kondo regime. The approach is innately simple and physically…

Strongly Correlated Electrons · Physics 2009-11-07 D. E. Logan , N. L. Dickens

Kondo effect is a prominent quantum phenomenon describing the many-body screening of a local magnetic impurity. Here, we reveal a new type of non-magnetic Kondo behavior generated by gauge fluctuations in strongly-correlated baths. We show…

Strongly Correlated Electrons · Physics 2021-12-15 Rui Wang , Yilin Wang , Y. X. Zhao , Baigeng Wang

In this paper we will investigate how one can create emergent curved spacetimes by locally tuning the coupling constants of condensed matter systems. In the continuum limit we thus obtain continuous effective quantum fields living on curved…

General Relativity and Quantum Cosmology · Physics 2011-12-22 Isabeau Prémont-Schwarz

A quantum dot with spin-orbit interaction can work as an efficient spin filter if it is connected to N (> 2) external leads via tunnel barriers. When an unpolarized current is injected to a quantum dot from a lead, polarized currents are…

Mesoscale and Nanoscale Physics · Physics 2010-12-30 Mikio Eto , Tomohiro Yokoyama

We report a strong Kondo effect (Kondo temperature ~ 4K) at high magnetic field in a selective area growth semiconductor quantum dot. The Kondo effect is ascribed to a singlet-triplet transition in the ground state of the dot. At the…

Mesoscale and Nanoscale Physics · Physics 2009-11-07 W. G. van der Wiel , S. De Franceschi , J. M. Elzerman , S. Tarucha , L. P. Kouwenhoven , J. Motohisa , F. Nakajima , T. Fukui

Orbital Kondo effect in a system of two single-level quantum dots attached to external electron reservoirs is considered theoretically. The dots are coupled via direct hoping term and Coulomb interaction. The Kondo temperature is evaluated…

Mesoscale and Nanoscale Physics · Physics 2010-09-28 Piotr Trocha

We examine the impact of Coulomb electron-electron interaction on transport in a junction with a quantum dot described by Kondo Hamiltonian. We analyze the Fermi liquid regime and consider the limit of zero temperature. With the help of…

Strongly Correlated Electrons · Physics 2009-11-11 A. Golub

In this work we implement the self-consistent Thomas-Fermi-Poisson approach to a homogeneous two dimensional electron system (2DES). We compute the electrostatic potential produced inside a semiconductor structure by a quantum-point-contact…

Mesoscale and Nanoscale Physics · Physics 2010-04-12 A. Siddiki F. Marquardt

We use a low-temperature scanning tunneling microscope to study the interplay between the Kondo effect of a single-atom contact and a spin current. To this end, a nickel tip is coated by a thick layer of copper and brought into contact with…

Strongly Correlated Electrons · Physics 2019-01-16 Deung-Jang Choi , Sébastien Guissart , Pascal Simon , Laurent Limot

Kondo correlation in a spin polarized quantum dot (QD) results from the dynamical formation of a spin singlet between the dot's net spin and a Kondo cloud of electrons in the leads, leading to enhanced coherent transport through the QD. We…

Mesoscale and Nanoscale Physics · Physics 2009-11-10 M. Avinun-Kalish , M. Heiblum , A. Silva , D. Mahalu , V. Umansky

This review illustrates how Local Fermi Liquid (LFL) theories describe the strongly correlated and coherent low-energy dynamics of quantum dot devices. This approach consists in an effective elastic scattering theory, accounting exactly for…

Mesoscale and Nanoscale Physics · Physics 2020-09-01 Michele Filippone , Arthur Marguerite , Karyn Le Hur , Gwendal Fève , Christophe Mora

We develop a unified theoretical description of the induced interaction and quantum noise in a system of two spins (qubits) coupled via a quasi-one-dimensional electron gas in the Luttinger liquid regime. Our results allow evaluation of the…

Mesoscale and Nanoscale Physics · Physics 2010-10-12 Dmitry Mozyrsky , Alexander Dementsov , Vladimir Privman

The compressibility of a two-dimensional electron system with spin in a spatially correlated random potential and a quantizing magnetic field is investigated. Electron-electron interaction is treated with the Hartree-Fock method. Numerical…

Mesoscale and Nanoscale Physics · Physics 2007-05-23 Alexander Struck , Bernhard Kramer

We investigate the persistent current influenced by the spin fluctuations in a mesoscopic ring weakly coupled to a quantum dot. It is shown that the Kondo effect gives rise to some unusual features of the persistent current in the limit…

Mesoscale and Nanoscale Physics · Physics 2009-10-31 Sam Young Cho , Kicheon Kang , Chul Koo Kim , Chang-Mo Ryu