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Related papers: Decoherence of two-electron spin states in quantum…

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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

The coherence time of an electron spin decohered by the nuclear spin environment in a quantum dot can be substantially increased by subjecting the electron to suitable dynamical decoupling sequences. We analyze the performance of high-level…

Mesoscale and Nanoscale Physics · Physics 2008-03-27 Wenxian Zhang , N. P. Konstantinidis , V. V. Dobrovitski , B. N. Harmon , Lea F. Santos , Lorenza Viola

The ability to design quantum systems that decouple from environmental noise sources is highly desirable for development of quantum technologies with optimal coherence. The chemical tunability of electronic states in magnetic molecules…

The interplay of optical driving and hyperfine interaction between an electron confined in a quantum dot and its surrounding nuclear spin environment produces a range of interesting physics such as mode-locking. In this work, we go beyond…

Mesoscale and Nanoscale Physics · Physics 2024-03-12 Arian Vezvaee , Gargee Sharma , Sophia E. Economou , Edwin Barnes

Decoherence of a localized electron spin in a solid state material (the ``central spin'' problem) at low temperature is believed to be dominated by interactions with nuclear spins in the lattice. This decoherence is partially suppressed…

Mesoscale and Nanoscale Physics · Physics 2009-11-13 W. M. Witzel , S. Das Sarma

Qubits, the quantum mechanical bits required for quantum computing, must retain their fragile quantum states over long periods of time. In many types of electron spin qubits, the primary source of decoherence is the interaction between the…

Mesoscale and Nanoscale Physics · Physics 2010-05-18 Hendrik Bluhm , Sandra Foletti , Izhar Neder , Mark Rudner , Diana Mahalu , Vladimir Umansky , Amir Yacoby

We describe a method for implementing deterministic quantum gates between two spin qubits separated by centimeters. Qubits defined by the singlet and triplet states of two exchange coupled quantum dots have recently been shown to possess…

Mesoscale and Nanoscale Physics · Physics 2009-11-11 Guido Burkard , Atac Imamoglu

In many realizations of electron spin qubits the dominant source of decoherence is the fluctuating nuclear spin bath of the host material. The slowness of this bath lends itself to a promising mitigation strategy where the nuclear spin bath…

Mesoscale and Nanoscale Physics · Physics 2010-11-30 Hendrik Bluhm , Sandra Foletti , Diana Mahalu , Vladimir Umansky , Amir Yacoby

The information in quantum computers is often stored in identical two-level systems (spins or pseudo-spins) that are separated by a distance shorter than the characteristic wavelength of a reservoir which is responsible for decoherence. In…

Quantum Physics · Physics 2016-09-08 Shoko Utsunomiya , Cyrus P. Master , Yoshihisa Yamamoto

We theoretically study the decoherence and the dynamical decoupling control of nitrogen-vacancy center electron spins in high-purity diamond, where the hyperfine interaction with $^{13}$C nuclear spins is the dominating decoherence…

Mesoscale and Nanoscale Physics · Physics 2015-03-19 Nan Zhao , Sai-Wah Ho , Ren-Bao Liu

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

We simulate the control of the spin states in a two-electron double quantum dot when an external detuning potential is used for passing the system through an anticrossing. The hyperfine coupling of the electron spins with the surrounding…

Mesoscale and Nanoscale Physics · Physics 2011-04-12 Jani Särkkä , Ari Harju

We study the decoherence of a spin in a quantum dot due to its hyperfine coupling to a randomly fluctuating bath of nuclear spins. The system is modelled by the central spin model with the spin bath initially being at infinite temperature.…

Mesoscale and Nanoscale Physics · Physics 2013-09-02 Alexandre Faribault , Dirk Schuricht

We systematically investigate the universal spin decoherence dynamics of a localized electron in an arbitrary nuclear spin bath, which can be even far away from equilibrium due to the weak nuclear-lattice interaction. We show that the…

Mesoscale and Nanoscale Physics · Physics 2008-06-27 Yi-Ya Tian , Pochung Chen , Daw-Wei Wang

In semiconductors, the T2* coherence time of a single confined spin is limited either by the fluctuating magnetic environment (via the hyperfine interaction), or by charge fluctuations (via the spin-orbit interaction). We demonstrate that…

Mesoscale and Nanoscale Physics · Physics 2012-04-13 K. M. Weiss , J. M. Elzerman , Y. L. Delley , J. Miguel-Sanchez , A. Imamoglu

Coherent two-level systems, or qubits, based on electron spins in GaAs quantum dots are strongly coupled to the nuclear spins of the host lattice via the hyperfine interaction. Realizing nuclear spin control would likely improve electron…

Mesoscale and Nanoscale Physics · Physics 2010-06-15 D. J. Reilly , J. M. Taylor , J. R. Petta , C. M. Marcus , M. P. Hanson , A. C. Gossard

We theoretically study the interaction of a heavy hole with nuclear spins in a quasi-two-dimensional III-V semiconductor quantum dot and the resulting dephasing of heavy-hole spin states. It has frequently been stated in the literature that…

Mesoscale and Nanoscale Physics · Physics 2008-11-03 Jan Fischer , W. A. Coish , D. V. Bulaev , Daniel Loss

The decoherence of mixed electron-nuclear spin qubits is a topic of great current importance, but understanding is still lacking: while important decoherence mechanisms for spin qubits arise from quantum spin bath environments with slow…

Mesoscale and Nanoscale Physics · Physics 2015-05-26 S. J. Balian , Gary Wolfowicz , John J. L. Morton , T. S. Monteiro

We present a study of the prospects for coherence preservation in solid-state spin qubits using dynamical decoupling protocols. Recent experiments have provided the first demonstrations of multipulse dynamical decoupling sequences in this…

Mesoscale and Nanoscale Physics · Physics 2013-05-29 M. J. Biercuk , H. Bluhm

The spin of an electron in a semiconductor quantum dot represents a natural nanoscale solid state qubit. Coupling to nuclear spins leads to decoherence that limits the number of allowed quantum logic operations for this qubit. Traditional…

Mesoscale and Nanoscale Physics · Physics 2016-07-13 Alexander Bechtold , Fuxiang Li , Kai Müller , Tobias Simmet , Per-Lennart Ardelt , Jonathan J. Finley , Nikolai A. Sinitsyn