近日，斯洛文尼亚约瑟夫·斯蒂芬研究所的Adám Bácsi与Rok itko合作并取得一项新进展。经过不懈努力，他们成功解决了林德布拉德形式论中光子浴存在时，通过正常和超导结的非弹性隧穿问题。相关研究成果已于2024年7月22日在国际知名学术期刊《物理评论A》上发表。

在这项工作中，研究人员解决了林德布拉德形式论中由于光子环境引起的非弹性隧穿问题，并介绍了如何在量子主方程方法中追踪光子自由度。由此产生的量子主方程是相同的参数化P（E）函数，不仅可以使研究人员获得电流，还有其他量，例如热电流，其是以一种系统和方便的方式。研究人员还证明，林德布拉德形式论提供了一个全面的描述波哥柳波夫准粒子通过超导结的隧穿，并适当地解释相干因素。如果态的正态密度是粒子-空穴不对称的，相干因子就变得重要。

据悉，电子隧穿过集成在电路中的结，会在光子场(电磁环境)中产生激发，并在此过程中损失能量。这种粒子的非弹性隧穿通常用P（E）理论来描述。在该理论的传统方法中，隧穿速率和通过结的电流，是使用费米黄金法则并通过对环境光子自由度的平均得到的。

附：英文原文

Title: Inelastic tunneling through normal and superconducting junctions in the presence of a photonic bath within the Lindbladian formalism

Author: Adám Bácsi, Rok itko

Issue&Volume: 2024/07/22

Abstract: An electron tunneling across a junction integrated into an electric circuit can generate an excitation in the photonic field (electromagnetic environment) and lose energy in the process. Such inelastic tunneling of particles is commonly described using theP（E）theory. In the conventional approach to this theory, the tunneling rate and the electric current through the junction are derived using Fermi's golden rule and by averaging over the environmental photonic degrees of freedom. In this work, we address the same problem of inelastic tunneling due to photonic environment in Lindbladian formalism and we present how the photonic degrees of freedom are traced out in the quantum master equation approach. The resulting quantum master equation is parametrized by the same P（E） function and enables us to obtain not only the electric current but various other quantities, for instance, the heat current, in a systematic and convenient way. We also demonstrate that the Lindbladian formalism provides a comprehensive description of Bogoliubov quasiparticle tunneling through superconducting junctions and that it properly accounts for the coherence factors. The coherence factors become important if the normal-state density of states is particle-hole asymmetric.

DOI: 10.1103/PhysRevA.110.012224

Source: https://journals.aps.org/pra/abstract/10.1103/PhysRevA.110.012224