论文标题
Weyl半法中的拓扑频率转换
Topological frequency conversion in Weyl semimetals
论文作者
论文摘要
从理论上讲，我们基于WEYL半学预测了一个新的工作原理，以进行光学扩增：当Weyl半准被两个频率以两个频率辐照时，接近Weyl点的电子通过[Martin等，PRX 7 041008（2017）通过拓扑频率转换的机理在频率之间转换能量。每个电子都以普朗克恒定的整数倍数乘以两个频率的乘积的整数倍数，以量化的速率转换能量。在模拟中，我们显示了最佳但可行的频带结构可以在“ THZ GAP”中以强度为$ 2 {\ rm w}/{\ rm mm^2} $在“ Thz Gap”中支持拓扑频率转换;当频率大于系统的松弛时间时，效果的增益可能会超过耗散损失。拓扑频率转换为光学扩增提供了新的范式，并进一步扩展了Weyl半学对技术应用的承诺。
We theoretically predict a new working principle for optical amplification, based on Weyl semimetals: when a Weyl semimetal is suitably irradiated at two frequencies, electrons close to the Weyl points convert energy between the frequencies through the mechanism of topological frequency conversion from [Martin et al, PRX 7 041008 (2017)]. Each electron converts energy at a quantized rate given by an integer multiple of Planck's constant multiplied by the product of the two frequencies. In simulations, we show that optimal, but feasible band structures can support topological frequency conversion in the "THz gap" at intensities down to $ 2{\rm W}/{\rm mm^2}$; the gain from the effect can exceed the dissipative loss when the frequencies are larger than the relaxation time of the system. Topological frequency conversion provides a new paradigm for optical amplification, and further extends Weyl semimetals' promise for technological applications.
