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The energy-level crossing behavior and quantum Fisher information in a quantum well with spin-orbit coupling.

ABSTRACT: We study the energy-level crossing behavior in a two-dimensional quantum well with the Rashba and Dresselhaus spin-orbit couplings (SOCs). By mapping the SOC Hamiltonian onto an anisotropic Rabi model, we obtain the approximate ground state and its quantum Fisher information (QFI) via performing a unitary transformation. We find that the energy-level crossing can occur in the quantum well system within the available parameters rather than in cavity and circuit quantum eletrodynamics systems. Furthermore, the influence of two kinds of SOCs on the QFI is investigated and an intuitive explanation from the viewpoint of the stationary perturbation theory is given.

SUBMITTER: Wang ZH

PROVIDER: S-EPMC4773991 | biostudies-other | 2016

REPOSITORIES: biostudies-other

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