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Related papers: Spin filtering through excited states in double qu…

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Constructive methods for controlling a coupled, two spin system via bounded amplitude, piecewise sinusoidal fields are provided. The fields are incident at the alrmor frequencies and take one of two phase values

Quantum Physics · Physics 2007-05-23 V. Ramakrishna , R. J. Ober , K. L. Flores , H. Rabitz

We demonstrate that spin current can be generated by an ac voltage in a one-channel quantum wire with strong repulsive electron interactions in the presence of a non-magnetic impurity and uniform static magnetic field. In a certain range of…

Mesoscale and Nanoscale Physics · Physics 2007-08-28 Bernd Braunecker , D. E. Feldman , Feifei Li

We demonstrate theoretically that the spin polarization of current can be electrically amplified within nonmagnetic semiconductors by exploiting the fact the spin current, compared to the charge current, is weakly perturbed by electric…

Mesoscale and Nanoscale Physics · Physics 2007-05-23 S. -W. Jung , H. -W. Lee

We put forward a mechanism for current induced spin polarization for a hole in a quantum dot side-coupled to a quantum wire, that is based on the spin-orbit splitting of the valence band. We predict that in a stark contrast with the…

Mesoscale and Nanoscale Physics · Physics 2021-07-15 V. N. Mantsevich , D. S. Smirnov

Spin effects in the transport properties of a quantum dot with spin-charge separation are investigated. It is found that the non-linear transport spectra are dominated by spin dynamics. Strong spin polarization effects are observed in a…

Strongly Correlated Electrons · Physics 2007-05-23 Alessandro Braggio , Maura Sassetti , Bernhard Kramer

In the optical pumping systems based on the pump-probe arrangement, the spin polarization of the atoms is generally monitored utilizing the probe laser beam, in which way an extra perturbation must be introduced and thus affects the normal…

Atomic Physics · Physics 2017-02-09 Jiancheng Fang , Rujie Li , Lihong Duan , Wenfeng Fan , Liwei Jiang

We discuss various methods of all-optical spin control in semiconductor quantum dots. We present different ways of rotating a single confined electron spin by optical coupling to a trion state. We also discuss a method for controlling the…

Mesoscale and Nanoscale Physics · Physics 2013-01-17 Pawel Machnikowski , Anna Grodecka , Carsten Weber , Andreas Knorr

We study charge and spin pumping in an interacting one-dimensional wire. We show that a spatially periodic potential modulated in space and time acts as a quantum pump inducing a dc-current component at zero bias. The current generated by…

Mesoscale and Nanoscale Physics · Physics 2009-11-10 R. Citro , N. Andrei , Q. Niu

We demonstrate that the spin-polarized electron current can interact with a microwave electric field in a resonant manner. The spin-orbit interaction gives rise to an effective magnetic field proportional to the electric current. In the…

Materials Science · Physics 2009-11-10 B. A. Glavin , K. W. Kim

We study adiabatic pumping through a two-level quantum dot with spin-orbit coupling. Using a diagrammatic real-time approach, we calculate both the pumped charge and spin for a periodic variation of the dot's energy levels in the limit of…

Mesoscale and Nanoscale Physics · Physics 2013-02-11 Stephan Rojek , Jürgen König , Alexander Shnirman

We have studied the spin-splitting effect in a four-terminal two-dimensional (2D) electron gas system with two potential barriers generated by two surface metal gates and an external perpendicular magnetic field. The calculations show that…

Mesoscale and Nanoscale Physics · Physics 2019-06-26 Zijiang Wang , Jianhong He , Huazhong Guo

The ability to control and exploit quantum coherence and entanglement drives research across many fields ranging from ultra-cold quantum gases to spin systems in condensed matter. Transcending different physical systems, optical approaches…

Mesoscale and Nanoscale Physics · Physics 2014-08-26 K. Müller , T. Kaldewey , R. Ripszam , J. S. Wildmann , A. Bechtold , M. Bichler , G. Koblmüller , G. Abstreiter , J. J. Finley

We propose a method to dynamically generate and control the flow of spin-entangled electrons, each belonging to a spin-singlet, by means of adiabatic quantum pumping. The pumping cycle functions by periodic time variation of localized…

Quantum Physics · Physics 2016-09-08 Kunal K. Das , Sungjun Kim , Ari Mizel

A dc current can be pumped through an interacting system by periodically varying two independent parameters such as magnetic field and a gate potential. We present a formula for the adiabatic pumping current in general interacting systems,…

Strongly Correlated Electrons · Physics 2015-06-25 Eran Sela , Yuval Oreg

We investigate two schemes for pumping spin adiabatically from a ferromagnet through an interacting quantum dot into a normal lead, which exploit the possibility to vary in time the ferromagnet's magnetization, either its amplitude or its…

Mesoscale and Nanoscale Physics · Physics 2013-05-17 Nina Winkler , Michele Governale , Jürgen König

The polarization of conduction electron spins due to an electrical current is observed in strained nonmagnetic semiconductors using static and time-resolved Faraday rotation. The density, lifetime, and orientation rate of the…

Mesoscale and Nanoscale Physics · Physics 2007-05-23 Y. Kato , R. C. Myers , A. C. Gossard , D. D. Awschalom

We have studied the current through a carbon nanotube quantum dot with one ferromagnetic and one normal-metal lead. For the values of gate voltage at which the normal lead is resonant with the single available non-degenerate energy level on…

Mesoscale and Nanoscale Physics · Physics 2008-08-20 Christopher A. Merchant , Nina Markovic

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

Magnetic noise from randomly fluctuating nuclear spin ensembles is the dominating source of decoherence for many multi-quantum-dot multielectron spin qubits. Here we investigate in detail the effect of a DC electric current on the coupled…

Mesoscale and Nanoscale Physics · Physics 2020-04-21 Jørgen Holme Qvist , Jeroen Danon

We study the spin polarization of mixed and entangled electron states in a four probe/beam splitter geometry with local Rashba and Dresselhaus interactions. A pair of maximally entangled electrons collides with the beam splitter and enters…

Quantum Physics · Physics 2012-12-04 Luis A. González-Árraga , Bertrand Berche , Ernesto Medina