Equilibration in closed quantum systems: Application to spin qubits

Abstract

We study an observable-based notion of equilibration and its application to realistic systems like spin qubits in quantum dots. On the basis of the so-called distinguishability, we analytically derive general equilibration bounds, which we relate to the standard deviation of the fluctuations of the corresponding observable. Subsequently, we apply these ideas to the central spin model describing the spin physics in quantum dots. We probe our bounds by analyzing the spin dynamics induced by the hyperfine interaction between the electron spin and the nuclear spins using exact diagonalization. Interestingly, even small numbers of nuclear spins as found in carbon or silicon based quantum dots are sufficient to significantly equilibrate the electron spin.

10 pages, 4 figures

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Cited by in corpus (9)

• Thermalization and prethermalization in isolated quantum systems: a theoretical overview
• Typical fast thermalization processes in closed many-body systems
• Equilibration time scales of physically relevant observables
• Equilibration time in many-body quantum systems
• Detection and characterization of Many-Body Localization in Central Spin Models
• Persisting correlations of a central spin coupled to large spin baths
• Equilibration of isolated many-body quantum systems with respect to general distinguishability measures
• Eigenstate Fluctuation Theorem in the Short and Long Time Regimes
• Strong frequency dependence of transport in the driven Fano-Anderson model