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Related papers: Spin bath-mediated decoherence in superconductors

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The reduced dynamics of a single or two qubits coupled to an interacting quantum spin bath modeled by a XXZ spin chain is investigated. By using the method of time-dependent density matrix renormalization group (t-DMRG), we go beyond the…

Strongly Correlated Electrons · Physics 2013-04-04 Cheng-Yan Lai , Jo-Tzu Hung , Chung-Yu Mou , Pochung Chen

The quantum coherence and gate fidelity of electron spin qubits in semiconductors is often limited by noise arising from coupling to a bath of nuclear spins. Isotopic enrichment of spin-zero nuclei such as $^{28}$Si has led to spectacular…

Understanding and mitigating decoherence is a key challenge for quantum science and technology. The main source of decoherence for solid-state spin systems is the uncontrolled spin bath environment. Here, we demonstrate quantum control of a…

Quantum Physics · Physics 2012-05-17 G. de Lange , T. van der Sar , M. S. Blok , Z. H. Wang , V. V. Dobrovitski , R. Hanson

The realization of spin-based logical gates crucially depends on magnetically-coupled spin qubits. Thus, understanding decoherence when spin qubits are in close proximity will become a roadblock to overcome. Herein, we provide a general…

Mesoscale and Nanoscale Physics · Physics 2019-08-21 L. Escalera-Moreno , A. Gaita-Ariño , E. Coronado

Silicon is promising for spin-based quantum computation because nuclear spins, a source of magnetic noise, may be eliminated through isotopic enrichment. Long spin decoherence times, $T_2$, have been measured in isotope-enriched silicon but…

Mesoscale and Nanoscale Physics · Physics 2010-10-29 Wayne M. Witzel , Malcolm S. Carroll , Andrea Morello , Lukasz Cywinski , S. Das Sarma

We investigate hyperfine-induced decoherence in a triangular spin-cluster for different qubit encodings. Electrically controllable eigenstates of spin chirality (C_z) show decoherence times that approach milliseconds, two orders of…

Mesoscale and Nanoscale Physics · Physics 2015-06-05 Filippo Troiani , Dimitrije Stepanenko , Daniel Loss

We consider the decoherence of a single localized electron spin due to its coupling to the lattice nuclear spin bath in a semiconductor quantum computer architecture. In the presence of an external magnetic field and at low temperatures,…

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

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

We investigate the performance of dynamical decoupling methods at suppressing electron spin decoherence from a low-temperature nuclear spin reservoir in a quantum dot. The controlled dynamics is studied through exact numerical simulation,…

Mesoscale and Nanoscale Physics · Physics 2009-11-13 Wenxian Zhang , V. V. Dobrovitski , Lea F. Santos , Lorenza Viola , B. N. Harmon

The works on decoherence due to spin baths usually agree in studying a one-spin system in interaction with a large spin bath. In this paper we generalize those models by analyzing a many-spin system and by studying decoherence or its…

Quantum Physics · Physics 2010-01-21 Mario Castagnino , Sebastian Fortin , Olimpia Lombardi

The problem of dipole-dipole decoherence of nuclear spins is considered for strongly entangled spin cluster. Our results show that its dynamics can be described as the decoherence due to interaction with a composite bath consisting of fully…

Quantum Physics · Physics 2007-05-23 A. Fedorov , L. Fedichkin

We investigate the decoherence properties of a central system composed of two spins 1/2 in contact with a spin bath. The dynamical regime of the bath ranges from a fully integrable integrable limit to complete chaoticity. We show that the…

Mesoscale and Nanoscale Physics · Physics 2009-11-13 A. Relano , J. Dukelsky , R. A. Molina

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

The decoherence of a central electron spin due to the dynamics of a coupled electron-spin bath is a core problem in solid-state spin physics. Ensemble experiments have studied the central spin coherence in detail, but such experiments…

We predict a spin pure dephasing channel in electron relaxation between states with unequal Zeeman splittings, exemplified by a spin-preserving electron tunneling between quantum dots in a magnetic field. The dephasing is caused by a…

Mesoscale and Nanoscale Physics · Physics 2018-08-07 Michał Gawełczyk , Mateusz Krzykowski , Krzysztof Gawarecki , Paweł Machnikowski

We numerically investigate decoherence of a two-spin system (central system) by a bath of many spins 1/2. By carefully adjusting parameters, the dynamical regime of the bath has been varied from quantum chaos to regular, while all other…

Quantum Physics · Physics 2009-11-10 J. Lages , V. V. Dobrovitski , B. N. Harmon

We demonstrate through exact solutions that a spin bath leads to stronger (faster) dephasing of a qubit than a bosonic bath with identical bath-coupling spectrum. This difference is due to the spin-bath "dressing" by the coupling.…

Quantum Physics · Physics 2011-06-10 D. D. Bhaktavatsala Rao , Gershon Kurizki

We experimentally demonstrate that the decoherence of a spin by a spin bath can be completely eliminated by fully polarizing the spin bath. We use electron paramagnetic resonance at 240 gigahertz and 8 Tesla to study the spin coherence time…

Quantum Physics · Physics 2009-11-13 Susumu Takahashi , Ronald Hanson , Johan van Tol , Mark S. Sherwin , David D. Awschalom

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

We study the decoherence of two coupled spins that interact with a spin-bath environment. It is shown that the connectivity and the coupling strength between the spins in the environment are of crucial importance for the decoherence of the…

Quantum Physics · Physics 2008-10-22 Shengjun Yuan , Mikhail I. Katsnelson , Hans De Raedt