English
Related papers

Related papers: Bound state in the continuum and spin filter in ar…

200 papers

A triangular triple quantum dot gives various Kondo effects, such as the emergence of an electric polarization accompanied by a complete compensation of spin degrees of freedom. The interplay of spin and charge of electrons in quantum dots…

Mesoscale and Nanoscale Physics · Physics 2016-06-03 Mikito Koga , Masashige Matsumoto , Hiroaki Kusunose

A novel scheme for spin filters is proposed by studying the coherent transport of electrons through the quantum wires with lateral magnetic modulations. Unlike other schemes in the literature, the modulation in our scheme is much weaker…

Condensed Matter · Physics 2007-05-23 J. Zhou , Q. W. Shi , M. W. Wu

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

We study the evolution and distribution of non-equilibrium electron spin polarization in n-type semiconductors within the two-component drift-diffusion model in an applied electric field. Propagation of spin-polarized electrons through a…

Mesoscale and Nanoscale Physics · Physics 2010-10-12 Yuriy V. Pershin , Vladimir Privman

We investigate non-linear magneto-transport through a single level quantum dot coupled to ferromagnetic leads, where the electron spin is coupled to a large, external (pseudo)spin via an anisotropic exchange interaction. We find regimes…

Mesoscale and Nanoscale Physics · Physics 2012-04-12 Carlos López-Monís , Clive Emary , Gerold Kiesslich , Gloria Platero , Tobias Brandes

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

The coherent spin dependent transport through a set of two capacitively coupled quantum dots placed in a magnetic field is considered within the equation of motion method. The magnetic field breaks the spin degeneracy. For special choices…

Mesoscale and Nanoscale Physics · Physics 2007-05-23 S. Lipinski , D. Krychowski

We report a study of spin dependent transport in a system composed of a quantum dot coupled to a normal metal lead and a ferromagnetic lead (NM-QD-FM). We use the master equation approach to calculate the spin-resolved currents in the…

Mesoscale and Nanoscale Physics · Physics 2007-05-23 F. M. Souza , J. C. Egues , A. P. Jauho

The spin-dependent conductance and spin-polarization of a MoS2 quantum dot are studied in presence (absent) of an external electric field perpendicular to the molybdenum plane. It is shown that in absence of the electric field, the…

Mesoscale and Nanoscale Physics · Physics 2015-01-06 Hamidreza Simchi , Mahdi Esmaeilzadeh , Hossein Mazidabadi , Mohammad Norouzi

A scheme of spin diode is proposed that uses a step-like quantum wire with Rashba spin-orbit interaction, connected to two leads with different width. It is shown that a very large vertical spin-polarized current can be generated when…

Mesoscale and Nanoscale Physics · Physics 2015-05-13 Xianbo Xiao , Yuguang Chen

Numerical calculations indicate that by suitably controlling the individual gate voltages of a capacitively coupled parallel double quantum dot, with each quantum dot coupled to one of two independent non-magnetic channels, this system can…

Mesoscale and Nanoscale Physics · Physics 2013-03-05 Carlos A. Busser , Adrian E. Feiguin , George B. Martins

We study the Kondo effect of a two-orbital vertical quantum dot (QD) coupled to two ferromagnetic leads by employing an equation of motion method. When the ferromagnetic leads are coupled with parallel spin polarization, we find three peaks…

Strongly Correlated Electrons · Physics 2011-04-19 Hitoshi Yoshizumi , Kensuke Inaba , Tomoko Kita , Sei-ichiro Suga

Coulomb and spin blockade spectroscopy investigations have been performed on an electrostatically defined ``artificial molecule'' connected to spin polarized leads. The molecule is first effectively reduced to a two-level system by placing…

Mesoscale and Nanoscale Physics · Physics 2009-11-10 M. Pioro-Ladriere , M. Ciorga , J. Lapointe , P. Zawadzki , M. Korkusinski , P. Hawrylak , A. S. Sachrajda

We use spatial spin separation by a magnetic focusing technique to probe the polarization of quantum point contacts. The point contacts are fabricated from p-type GaAs/AlGaAs heterostructures. A finite polarization is measured in the…

Mesoscale and Nanoscale Physics · Physics 2009-11-11 L. P. Rokhinson , L. N. Pfeiffer , K. W. West

We study the effect of an external magnetic field in the Kondo regime of a double-quantum-dot system in which a strongly correlated dot (the "hanging dot") is coupled to a second, noninteracting dot that also bridges the gap between two…

Mesoscale and Nanoscale Physics · Physics 2013-06-13 Luis G. G. V. Dias da Silva , Edson Vernek , Kevin Ingersent , Nancy P. Sandler , Sergio E. Ulloa

By measuring electron tunneling between a ferromagnet and individual energy levels in an aluminum quantum dot, we show how spin-resolved quantum states can be used as filters to determine spin-dependent tunneling rates. We also observe…

Mesoscale and Nanoscale Physics · Physics 2009-11-07 Mandar M. Deshmukh , D. C. Ralph

Polymerized quantum spin chains (i.e. spin chains with a periodic modulation of the coupling constants) exhibit plateaux in their magnetization curves when subjected to homogeneous external magnetic fields. We argue that the strong-coupling…

Strongly Correlated Electrons · Physics 2009-10-31 A. Honecker

We implement a microscopic spin filter for cold fermionic atoms in a quantum point contact (QPC) and create fully spin-polarized currents while retaining conductance quantization. Key to our scheme is a near-resonant optical tweezer…

We study the existence of bound states in the continuum for a system of n two-level quantum emitters, coupled with a one-dimensional boson field, in which a single excitation is shared among different components of the system. The emitters…

Quantum Physics · Physics 2019-08-27 Paolo Facchi , Davide Lonigro , Saverio Pascazio , Francesco V. Pepe , Domenico Pomarico

We formulate a model of a semiconductor Quantum Dot laser with injection of spin-polarized electrons. As compared to higher-dimensionality structures, the Quantum-Dot-based active region is known to improve laser properties, including the…

Mesoscale and Nanoscale Physics · Physics 2010-09-03 Rafał Oszwałdowski , Christian Gøthgen , Igor Žutić