光场作用下双势阱中隧道效应淬灭以及相位相干作用的研究

Quenching of tunneling and role of phase coherent in a double-well using laser fields

利用二能级近似,研究了受驱动光场作用时的粒子在双势阱中的量子隧道效应抑制现象.讨论了远共振激发和强场激发情况下的粒子定域问题.在远共振领域,得出了忽略耦合项的系统随时间演化的无微扰表达式,特别是在强场领域,由于贝塞尔函数的渐近行为,在远共振条件不满足时结论仍然成立,即零阶贝塞尔函数为零时,系统将发生相干隧穿抑制现象.

Some aspects of quantum tunneling of a particle in a double-well driven by an external field are studied within the two level approximations. The localization problems of particles are studied when the system are driven by far off-resonance and/or strong laser fields. A nonperturbative expression of the time evolution of system regardless of the coupling strength value is obtained, in the strong field regime, because of the asymptotic behavior of the Bessel function, the conclusion remain valid even when the far off-resonance condition is not fulfilled. That, when the zeros Bessel function vanishes, coherent destruction of tunneling will occur.Instead of discuss the two limitations one by one, simple expression with profound meaning is given.