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arXiv · 1502.03403

Coherent destruction of tunneling in a lattice array with controllable boundary

Liping Li·Xiaobing Luo·Xin-You Lü·Xiaoxue Yang·Ying Wu
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Abstract

We have investigated how the dynamics of a quantum particle initially localized in the left boundary site under periodic driving can be manipulated via control of the right boundary site of a lattice array. Because of the adjustable coupling between the right boundary site and its nearest-neighbor, we can realize either coherent destruction of tunneling to coherent tunneling (CDT-CT) transition or coherent tunneling to coherent destruction of tunneling (CT-CDT) transition, by driving or moving the right boundary site while keeping the left boundary site driven by a periodically oscillating field with a fixed driving parameter. In particular, the transition direction shows odd-even sensitivity to the number of lattice sites. We have also revealed that our proposed CDT-CT transition is robust against the second order coupling (SOC) between next-nearest-neighbor sites in odd-$N$-site systems, whereas localization can be significantly enhanced by SOC in even-$N$-site systems. More interestingly, it is found destruction and revival of CDT observable in non-high-frequency regimes. Our results can be readily verified within the capacity of current experiments.

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Liping Li, Xiaobing Luo, Xin-You Lü, Xiaoxue Yang, Ying Wu. 2016-01-12. Coherent destruction of tunneling in a lattice array with controllable boundary. https://doi.org/10.1103/physreva.91.063804

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