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Related papers: Phonon Dephasing, Entanglement and Exchange-Only T…

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We report on simulations of the degree of polarization entanglement of photon pairs simultaneously emitted from a quantum dot-cavity system that demand revisiting the role of phonons. Since coherence is a fundamental precondition for…

Mesoscale and Nanoscale Physics · Physics 2019-09-26 Tim Seidelmann , Florian Ungar , Andreas M. Barth , Alexei Vagov , Vollrath Martin Axt , Moritz Cygorek , Tilmann Kuhn

We study the two-qubit controlled-not gate operating on qubits encoded in the spin state of a pair of electrons in a double quantum dot. We assume that the electrons can tunnel between the two quantum dots encoding a single qubit, while…

Mesoscale and Nanoscale Physics · Physics 2007-05-23 Dimitrije Stepanenko , Guido Burkard

Entangled qubits transported through space is a key element in many prospective quantum information systems, from long-distance quantum communication to large modular quantum processors. The moving qubits are decohered by time- and…

Mesoscale and Nanoscale Physics · Physics 2024-09-09 Aleksandr S. Mokeev , Yu-Ning Zhang , Viatcheslav V. Dobrovitski

Realizing perfect two-photon entanglement from quantum dots has been a long-standing scientific challenge. It is generally thought that the nuclear spins limit the entanglement fidelity through spin flip dephasing processes. However, this…

One of the key pathways towards scalability of spin-based quantum computing systems lies in achieving long-range interactions between electrons and increasing their inter-connectivity. Coherent spin transport is one of the most promising…

Quantum systems under electric fields provide a powerful framework for uncovering and controlling novel quantum phases, especially in low-dimensional systems with strong correlations. In this work, we investigate quantum phase transitions…

Strongly Correlated Electrons · Physics 2025-05-22 D. Arisa , R. M. Dos Santos , Isaac M. Carvalho , Vivian V. França

We investigate electron charge decoherence in a laterally-coupled single-electron semiconductor double quantum dot through electron-phonon interaction. We analytically and numerically evaluate the relaxation and dephasing rates due to…

Mesoscale and Nanoscale Physics · Physics 2009-11-11 V. N. Stavrou , Xuedong Hu

Semiconductor quantum dots have emerged as an especially promising platform for the generation of polarization-entangled photon pairs. However, it was demonstrated recently that the two-photon excitation scheme employed in state-of-the-art…

We investigate the influence of the electron-phonon interaction on the decay dynamics of a quantum dot coupled to an optical microcavity. We show that the electron-phonon interaction has important consequences on the dynamics, especially…

Mesoscale and Nanoscale Physics · Physics 2012-08-17 P. Kaer , T. R. Nielsen , P. Lodahl , A. -P. Jauho , J. Mork

We study the asymptotic dynamics of a driven quantum two level system coupled via a quantum detector to the environment. We find multi-photon resonances which are due to the entanglement of the qubit and the detector. Different regimes are…

Mesoscale and Nanoscale Physics · Physics 2009-11-10 M. C. Goorden , M. Thorwart , M. Grifoni

We investigate the usefulness and viability of the scheme developed by Viola and Lloyd [Phys. Rev. A 58, 2733 (1998)] to control dephasing in the context of exciton-based quantum computation with self-assembled quantum dots. We demonstrate…

Mesoscale and Nanoscale Physics · Physics 2008-03-31 Thomas E. Hodgson , Lorenza Viola , Irene D'Amico

The Heisenberg exchange interaction between neighboring quantum dots allows precise voltage control over spin dynamics, due to the ability to precisely control the overlap of orbital wavefunctions by gate electrodes. This allows the study…

We study the decay of entanglement of quantum dot electron-spin qubits under hyperfine interaction mediated decoherence. We show that two qubit entanglement of a single entangled initial state may exhibit decay characteristic of the two…

Quantum Physics · Physics 2014-06-25 Paweł Mazurek , Katarzyna Roszak , Ravindra W. Chhajlany , Paweł Horodecki

We study the effect of phonons on a proposed scheme for the direct measurement of two-electron spin states in a double quantum dot by monitoring the the noise of the current flowing through a quantum point contact coupled to one of the…

Quantum Physics · Physics 2015-04-01 Katarzyna Roszak , Łukasz Marcinowski , Paweł Machnikowski

We present an approach for entangling electron spin qubits localized on spatially separated impurity atoms or quantum dots via a multi-electron, two-level quantum dot. The effective exchange interaction mediated by the dot can be understood…

Mesoscale and Nanoscale Physics · Physics 2015-06-10 V. Srinivasa , H. Xu , J. M. Taylor

Full electrical control of quantum bits could enable fast, low-power, scalable quantum computation. Although electric dipoles are highly attractive to couple spin qubits electrically over long distances, mechanisms identified to control…

Mesoscale and Nanoscale Physics · Physics 2018-07-05 J. C. Abadillo-Uriel , Joe Salfi , Xuedong Hu , Sven Rogge , M. J. Calderón , Dimitrie Culcer

We analyze the unitary time evolution of a conduction electron, described by a two-level system, interacting with two-level systems (spins) through a spin-spin interaction and prove that coherent spin states of the conduction electron are…

Mesoscale and Nanoscale Physics · Physics 2009-11-07 Marco Frasca

We study quenches of the interaction and electron-phonon coupling parameter in the Hubbard-Holstein model, using nonequilibrium dynamical mean field theory. The calculations are based on a generalized Lang-Firsov scheme for time-dependent…

Strongly Correlated Electrons · Physics 2013-10-11 Philipp Werner , Martin Eckstein

We study the disentanglement of two spin qubits which interact with a general XY spin-chain environment. The dynamical process of the disentanglement is numerically and analytically investigated in the vicinity of quantum phase transition…

Quantum Physics · Physics 2009-11-13 Zi-Gang Yuan , Ping Zhang , Shu-Shen Li

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