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Spectral properties and magneto-optical excitations in semiconductor double-rings under Rashba spin-orbit interaction

Wen-Hsuan Kuan·Chi-Shung Tang·Cheng-Hung Chang
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Abstract

We have numerically solved the Hamiltonian of an electron in a semiconductor double ring subjected to the magnetic flux and Rashba spin-orbit interaction. It is found that the Aharonov-Bohm energy spectrum reveals multi-zigzag periodic structures. The investigations of spin-dependent electron dynamics via Rabi oscillations in two-level and three-level systems demonstrate the possibility of manipulating quantum states. Our results show that the optimal control of photon-assisted inter-ring transitions can be achieved by employing cascade-type and $Λ$-type transition mechanisms. Under chirped pulse impulsions, a robust and complete transfer of an electron to the final state is shown to coincide with the estimation of the Landau-Zener formula.

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Wen-Hsuan Kuan, Chi-Shung Tang, Cheng-Hung Chang. 2007-03-24. Spectral properties and magneto-optical excitations in semiconductor double-rings under Rashba spin-orbit interaction. https://doi.org/10.1103/physrevb.75.155326

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