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W. -X. Yan

Publications and source records attributed to W. -X. Yan.

3 recordsLinked to original sources

Tuning the quantum tunneling and quantum information properties among the trion states in coupled quantum dots

Quantum transition and information properties of the Coulomb coupled trion (electron-electron-hole) in the double quantum dots under the influence of the time-dependent electric field have been studied. Tuning the Hubbard interaction strength amongst the states of electron-hole complexes and the parameters of the ac field, two strikingly different kinds of approximate qubit can be constructed within the eight trion states. The similarity and difference between the electron dynamic entanglement and overlapping of the wavefunction with the Bell state have been elucidated through analyzing these two kinds of qubit.

quant-ph

Zener Transitions Between Dissipative Bloch Bands

Within a two-band tight binding model, we investigate the dynamics of electrons with Markoffian dephasing under the influence of static electric fields. With the help of both numerical and analytic calculations we find that the dephasing ultimately takes electrons which are initially located in one miniband to equal population of the two minibands, instead of undergoing persistent Rabi flop, as they do in the absence of scattering. Miniband localization is wholly destroyed by the intervention of dephasing. We also obtain the effective decay time for the approach to equal band populations under conditions of small interband communication and in the long-time limit, through a perturbative calculation. The decay rate shows characteristic sharp peaks at values of the parameters which give Zener resonances.

cond-mat.mes-hall