操纵Floquet驱动的拓绝缘器与非共振圆极化光在存在的六边形费米表面曲
1Department of Physics, University of Allahabad, Prayagraj 211002, India.
Journal of physics. Condensed matter : an Institute of Physics journal
|November 29, 2024
概括
用圆极化光照射拓绝缘体会改变它们的拓性质. 这项研究揭示了光是如何发光的.
科学领域:
- 凝聚物质物理学 凝聚物质物理学
- 拓学材料科学科学 拓学材料科学
- 量子光学是一种量子光学.
背景情况:
- 拓绝缘器具有独特的表面状态,具有受保护的电子特性.
- 用光驱动这些系统可以诱导新的拓阶段.
- 了解光物质相互作用是控制拓状态的关键.
研究的目的:
- 为了研究圆极化光对拓绝缘体表面状态的影响.
- 探索拓不变量的修改,如弗洛克特的切尔恩数.
- 用光识别控制拓相位过渡的机制.
主要方法:
- 弗洛克理论应用于具有六角曲线的迪拉克费米子哈密尔顿式.
- 对于驱动的拓绝缘体表面状态的有效哈密尔顿推导.
- 计算贝里曲率和异常的霍尔导电性.
主要成果:
- 确定了一种依赖于螺旋和圆的质量项,打破了时间逆向对称.
- 这个质量项的符号,因此拓相,可以通过光极化调节.
- 异常的霍尔导电性显示出对光圆度和振幅的强烈依赖.
结论:
- 圆极化光是一种强大的工具,可以动态控制绝缘体的拓性质.
- 这项工作为光工学的拓量子态铺平了道路.
- 可调节的拓相可以在未来的电子和自旋电子设备中得到应用.
相关概念视频
Fermi Level Dynamics
225
The vacuum level denotes the energy threshold required for an electron to escape from a material surface. It is usually positioned above the conduction band of a semiconductor and acts as a benchmark for comparing electron energies within various materials.
Electron affinity in semiconductors refers to the energy gap between the minimum of its conduction band and the vacuum level and it is a critical parameter in determining how easily a semiconductor can accept additional electrons.
The work...
Electron affinity in semiconductors refers to the energy gap between the minimum of its conduction band and the vacuum level and it is a critical parameter in determining how easily a semiconductor can accept additional electrons.
The work...
225
Potential Due to a Polarized Object
366
A neutral atom consists of a positively charged nucleus surrounded by a negatively charged electron cloud. When placed in an external electric field, the external electric force pulls the electrons and nucleus apart, opposite to the intrinsic attraction between the nucleus and the electrons. The opposing forces balance each other with a slight shift between the center of masses of the nucleus and the electron cloud, resulting in a polarized atom. On the other hand, a few molecules, like water,...
366
Fermi Level
503
The Fermi-Dirac function is represented by an S-shaped curve indicating the probability of an energy state being occupied by an electron at a given temperature. The Fermi level is the energy level at which there is a fifty percent chance of finding an electron, and it is positioned between the lower-energy valence band and the higher-energy conduction band.
At absolute zero temperature, electrons fill all energy states up to the Fermi level, leaving upper states empty. As the temperature rises,...
At absolute zero temperature, electrons fill all energy states up to the Fermi level, leaving upper states empty. As the temperature rises,...
503
Induced Electric Dipoles
4.2K
A permanent electric dipole orients itself along an external electric field. This rotation can be quantified by defining the potential energy because the external torque does work in rotating it. Then, the potential energy is minimum at the parallel configuration and maximum at the antiparallel configuration. While the former is a stable equilibrium, the latter is an unstable equilibrium.
Since the absolute value of potential energy holds no physical meaning, its zero value can be chosen as per...
Since the absolute value of potential energy holds no physical meaning, its zero value can be chosen as per...
4.2K


