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arXiv · 1109.5622

Coherent destruction of tunneling in a lattice array under selective in-phase modulations

Xiaobing Luo·Jiahao Huang·Chaohong Lee
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Abstract

We explore the coherent destruction of tunneling (CDT) in a lattice array under selective in-phase harmonic modulations, in which some selected lattice sites are driven by in-phase harmonic oscillating fields and other lattice sites are undriven. Due to the occurrence of CDT, if the driving amplitude $A$ and the driving frequency $ω$ are tuned to satisfy the zeroth-order Bessel function $J_0(A/ω)=0$, the driven lattice sites are approximately decoupled with the undriven lattice sites. The CDT even takes place in lattice systems with high-order couplings between non-nearest lattice sites. By using the CDT, we propose a scheme for realizing directed transport of a single particle. It is possible to observe the CDT in the engineered optical waveguide array, which provides a new opportunity for controlling light propagation and designing switch-like couplers.

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Xiaobing Luo, Jiahao Huang, Chaohong Lee. 2011-10-27. Coherent destruction of tunneling in a lattice array under selective in-phase modulations. https://doi.org/10.1103/physreva.84.053847

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