Moreira Saulo V, Marques Breno, Semião Fernando L
Department of Physics and NanoLund, Lund University, Box 118, 22100 Lund, Sweden.
Centro de Ciências Naturais e Humanas, Universidade Federal do ABC-UFABC, Santo André 09210-580, Brazil.
Entropy (Basel). 2021 Sep 8;23(9):1179. doi: 10.3390/e23091179.
The investigation of the phenomenon of dephasing assisted quantum transport, which happens when the presence of dephasing benefits the efficiency of this process, has been mainly focused on Markovian scenarios associated with constant and positive dephasing rates in their respective Lindblad master equations. What happens if we consider a more general framework, where time-dependent dephasing rates are allowed, thereby, permitting the possibility of non-Markovian scenarios? Does dephasing-assisted transport still manifest for non-Markovian dephasing? Here, we address these open questions in a setup of coupled two-level systems. Our results show that the manifestation of non-Markovian dephasing-assisted transport depends on the way in which the incoherent energy sources are locally coupled to the chain. This is illustrated with two different configurations, namely non-symmetric and symmetric. Specifically, we verify that non-Markovian dephasing-assisted transport manifested only in the non-symmetric configuration. This allows us to draw a parallel with the conditions in which time-independent Markovian dephasing-assisted transport manifests. Finally, we find similar results by considering a controllable and experimentally implementable system, which highlights the significance of our findings for quantum technologies.
退相辅助量子输运现象的研究主要集中在与各自林德布拉德主方程中恒定且正的退相率相关的马尔可夫情形，这种现象发生在退相的存在有利于该过程的效率时。如果我们考虑一个更一般的框架，即允许随时间变化的退相率，从而允许非马尔可夫情形的可能性，会发生什么呢？对于非马尔可夫退相，退相辅助输运是否仍然会表现出来？在这里，我们在耦合二能级系统的设置中解决这些开放性问题。我们的结果表明，非马尔可夫退相辅助输运的表现取决于非相干能量源与链局部耦合的方式。这通过两种不同的配置来说明，即非对称和对称配置。具体来说，我们验证了非马尔可夫退相辅助输运仅在非对称配置中表现出来。这使我们能够与与时间无关的马尔可夫退相辅助输运表现出来的条件进行类比。最后，我们通过考虑一个可控且可实验实现的系统得到了类似的结果，这突出了我们的发现对量子技术的重要性。
