Pattanayak Adhip, Pujari Sumiran, Dixit Gopal
Department of Physics, Indian Institute of Technology Bombay, Powai, Mumbai, 400076, India.
Sci Rep. 2022 Apr 25;12(1):6722. doi: 10.1038/s41598-022-10465-9.
The observation of Majorana fermions as collective excitations in condensed-matter systems is an ongoing quest, and several state-of-the-art experiments have been performed in the last decade. As a potential avenue in this direction, we simulate the high-harmonic spectrum of Kitaev's superconducting chain model that hosts Majorana edge modes in its topological phase. It is well-known that this system exhibits a topological-trivial superconducting phase transition. We demonstrate that high-harmonic spectroscopy is sensitive to the phase transition in presence of open boundary conditions due to the presence or absence of these edge modes. The population dynamics of the Majorana edge modes are different from the bulk modes, which is the underlying reason for the distinct harmonic profile of both the phases. On the contrary, in presence of periodic boundary conditions with only bulk modes, high-harmonic spectroscopy becomes insensitive to the phase transition with similar harmonic profiles in both phases.
在凝聚态系统中观测马约拉纳费米子作为集体激发是一项正在进行的探索，并且在过去十年中已经开展了若干前沿实验。作为朝着这个方向的一条潜在途径，我们模拟了基塔耶夫超导链模型的高次谐波谱，该模型在其拓扑相中存在马约拉纳边缘模式。众所周知，这个系统呈现出拓扑平凡的超导相变。我们证明，由于这些边缘模式的存在或不存在，在存在开放边界条件的情况下，高次谐波光谱对相变敏感。马约拉纳边缘模式的布居动力学与体态模式不同，这是两个相具有不同谐波分布的根本原因。相反，在仅存在体态模式的周期性边界条件下，高次谐波光谱对相变变得不敏感，两个相具有相似的谐波分布。
