Baykusheva Denitsa, Chacón Alexis, Lu Jian, Bailey Trevor P, Sobota Jonathan A, Soifer Hadas, Kirchmann Patrick S, Rotundu Costel, Uher Ctirad, Heinz Tony F, Reis David A, Ghimire Shambhu
Stanford PULSE Institute, SLAC National Accelerator Laboratory, Menlo Park, California 94025, United States.
Center for Nonlinear Studies and Theoretical Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, United States.
Nano Lett. 2021 Nov 10;21(21):8970-8978. doi: 10.1021/acs.nanolett.1c02145. Epub 2021 Oct 22.
We report the observation of an anomalous nonlinear optical response of the prototypical three-dimensional topological insulator bismuth selenide through the process of high-order harmonic generation. We find that the generation efficiency increases as the laser polarization is changed from linear to elliptical, and it becomes maximum for circular polarization. With the aid of a microscopic theory and a detailed analysis of the measured spectra, we reveal that such anomalous enhancement encodes the characteristic topology of the band structure that originates from the interplay of strong spin-orbit coupling and time-reversal symmetry protection. The implications are in ultrafast probing of topological phase transitions, light-field driven dissipationless electronics, and quantum computation.
我们报告了通过高次谐波产生过程对典型三维拓扑绝缘体硒化铋的异常非线性光学响应的观测。我们发现，随着激光偏振从线性变为椭圆，产生效率会提高，并且在圆偏振时达到最大值。借助微观理论和对测量光谱的详细分析，我们揭示了这种异常增强编码了源自强自旋轨道耦合和时间反演对称性保护相互作用的能带结构的特征拓扑。其意义在于拓扑相变的超快探测、光场驱动的无耗散电子学以及量子计算。
