论文标题
耦合的非铁踢转子的定向动量电流和弹道能扩散的共存
Coexistence of directed momentum current and ballistic energy diffusion in coupled non-Hermitian kicked rotors
论文作者
论文摘要
我们用$ \ Mathcal {pt} $ - 对称电位中的耦合脚踢转子中的量子传输进行数值研究。我们发现，当复杂电势的假想部分的振幅超出了阈值时，就会出现自发的$ \ mathcal {pt} $ - 对对称性的破坏，这可以通过有效的耦合强度来调节。在$ \ Mathcal {pt} $ - 对称性破坏的状态下，由周期踢球驱动的粒子在动量空间中单向移动，表明有向电流的出现。同时，随着耦合强度的提高，我们发现从弹道能扩散到一种修饰的弹道能扩散的过渡，其中波袋的宽度也随着电力法的时间而增加。我们的发现表明，粒子间耦合与非铁级驾驶潜力之间的相互作用引起的变质效应是这些特定运输行为的原因。
We numerically investigate the quantum transport in a coupled kicked rotors with the $\mathcal{PT}$-symmetric potential. We find that the spontaneous $\mathcal{PT}$-symmetry breaking of wavefunctions emerges when the amplitude of the imaginary part of the complex potential is beyond a threshold value, which can be modulated by the coupling strength effectively. In the regime of the $\mathcal{PT}$-symmetry breaking, the particles driven by the periodical kicks move unidirectionally in momentum space, indicating the emergence of a directed current. Meanwhile, with increasing the coupling strength, we find a transition from the ballistic energy diffusion to a kind of the modified ballistic energy diffusion where the width of the wavepacket also increases with time in a power law. Our findings suggest that the decoherence effect induced by the interplay between the inter-particle coupling and the non-Hermitian driving potential is responsible for these particular transport behaviors.
