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Related papers: Pure spin decoherence in quantum dots

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Quantum states are described by wave functions whose phases cannot be directly measured, but which play a vital role in quantum effects such as interference and entanglement. The loss of the relative phase information, termed decoherence,…

Chemical Physics · Physics 2019-12-20 Jia Chen , Cong Hu , John F. Stanton , Stephen Hill , Hai-Ping Cheng , Xiao-Guang Zhang

Optimized light-matter coupling in semiconductor nanostructures is a key to understand their optical properties and can be enabled by advanced fabrication techniques. Using in-situ electron beam lithography combined with a low-temperature…

Quantum decoherence happens when the system interacts with the environment. Quantum correlation behaviours in the two-qubit spin squeezing model are studied under the influence of intrinsic decoherence. Quantitative results were determined,…

Quantum Physics · Physics 2023-03-07 Venkat Abhignan , R. Muthuganesan

We theoretically consider coherence times for spins in two quantum computer architectures, where the qubit is the spin of an electron bound to a P donor impurity in Si or within a GaAs quantum dot. We show that low temperature decoherence…

Mesoscale and Nanoscale Physics · Physics 2009-11-07 Rogerio de Sousa , S. Das Sarma

Realising scalable quantum networks requires a meticulous level of understanding and mitigating the deleterious effects of decoherence. Many quantum device platforms feature multiple decoherence mechanisms, often with a dominant mechanism…

Quantum Physics · Physics 2023-08-17 Julian Wiercinski , Erik M. Gauger , Moritz Cygorek

We generalize the scattering theory of quantum shot noise to include the full spin-density matrix of electrons injected from a spin-filtering or ferromagnetic electrode into a quantum-coherent nanostructure governed by various…

Mesoscale and Nanoscale Physics · Physics 2007-05-23 Ralitsa L. Dragomirova , Branislav K. Nikolic

We investigate the temperature dependence of photon coherence properties through two photon interference (TPI) measurements from a single QD under resonant excitation. We show that the loss of indistinguishability is only related to the…

We consider here the problem of a "central spin", with spin quantum number $S \gg 1$, interacting with a set of microscopic spins. Interactions between the microscopic spins are ignored. This model describes magnetic grains or magnetic…

Condensed Matter · Physics 2016-08-31 N. V. Prokof'ev , P. C. E. Stamp

We investigate phonon-induced spin and charge relaxation mediated by spin-orbit and hyperfine interactions for a single electron confined within a double quantum dot. A simple toy model incorporating both direct decay to the ground state of…

Mesoscale and Nanoscale Physics · Physics 2014-07-04 V. Srinivasa , K. C. Nowack , M. Shafiei , L. M. K. Vandersypen , J. M. Taylor

Spin-orbit coupling in solids is typically a single-body effect arising from relativity. In this work, we propose a spontaneous generation of spin-orbit coupling from symmetry breaking. A spin-dependent electron-phonon coupling model is…

Strongly Correlated Electrons · Physics 2024-10-23 Xiangyu Zhang , Da Wang , Congjun Wu

We study spin relaxation and decoherence caused by electron-lattice and spin-orbit interaction and predict striking effects induced by magnetic fields $B$. For particular values of $B$, destructive interference occurs resulting in ultralong…

Mesoscale and Nanoscale Physics · Physics 2008-06-04 Denis V. Bulaev , Bjoern Trauzettel , Daniel Loss

We study the kinetics of spin coherence of optically excited electrons in an undoped insulating ZnSe/Zn$_{1-x}$Cd$_x$Se quantum well under moderate magnetic fields in the Voigt configuration. After clarifying the optical coherence and the…

Condensed Matter · Physics 2009-10-31 M. W. Wu , H. Metiu

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

Phonon-induced orbital and spin relaxation rates of single electron states in lateral single and double quantum dots are obtained numerically for realistic materials parameters. The rates are calculated as a function of magnetic field and…

Mesoscale and Nanoscale Physics · Physics 2007-05-23 Peter Stano , Jaroslav Fabian

Spin qubits in Silicon quantum dots can have long coherence times, yet their manipulation relies on the exchange interaction, through which charge noise can induce decoherence. Charge traps near the interface of a Si heterostructure lead to…

Mesoscale and Nanoscale Physics · Physics 2015-05-13 Dimitrie Culcer , Xuedong Hu , S. Das Sarma

We show that singlet-triplet superpositions of two-electron spin states in a double quantum dot undergo a phonon-induced pure dephasing which relies only on the tunnel coupling between the dots and on the Pauli exclusion principle. As such,…

Mesoscale and Nanoscale Physics · Physics 2010-09-15 Katarzyna Roszak , Pawel Machnikowski

A pair of coupled dots with one electron in each dot can provide improvements in spin coherence, particularly at an electrical bias called the sweet spot, but few measurements have been performed on self-assembled dots in this regime. Here,…

Mesoscale and Nanoscale Physics · Physics 2022-02-17 Kha X. Tran , Allan S. Bracker , Michael K. Yates , Joel Q. Grim , Samuel G. Carter

The effects resulting due to dressing of an exciton with phonons are analysed as the source of unavoidable decoherence of orbital degrees of freedom in quantum dots. The dressing with longitudinal optical phonons results in energetic shift…

Mesoscale and Nanoscale Physics · Physics 2007-05-23 L. Jacak , A. Janutka , J. Krasnyj , P. Machnikowski , A. Radosz

The nuclear spin of a phosphorus atom in silicon has been used as a quantum bit in various quantum-information experiments. It has been proposed that this nuclear-spin qubit can be efficiently controlled by an ac electric field, when…

Mesoscale and Nanoscale Physics · Physics 2019-10-02 Bence Hetényi , Péter Boross , András Pályi

We study spin-orbit mediated relaxation and dephasing of electron spins in quantum dots. We show that higher order contributions provide a relaxation mechanism that dominates for low magnetic fields and is of geometrical origin. In the…

Mesoscale and Nanoscale Physics · Physics 2007-05-23 Pablo San-Jose , Gergely Zarand , Alexander Shnirman , Gerd Schön