论文标题
通过原子放大发射并在光子时间晶体中激光
Amplified Emission by Atoms and Lasing in Photonic Time Crystals
论文作者
论文摘要
光子时间晶体（PTCS） - 带有折射率调制的介电介质会定期调制，在时间反射和动量带盖引起的光子学上提供新的机会。在这里，我们研究了PTC内部辐射源的光的发射。我们在时间变化的培养基中解决了发射的一般经典和量子机械模型，并发现当与动量间隙相关联时，辐射始终会呈指数增大，无论是由宏观源，原子还是通过真空波动引发的，都会从调制中获取放大能量。随着时间的流逝，辐射线宽变得更窄，并以动量差距的中心为中心。我们计算了嵌入PTC中的原子的自发衰减速率，并表明由于光子状态的低密度，它在带边缘消失了。最后，我们提出了非共振可调PTC激光器的概念。
Photonic Time Crystals (PTCs) - dielectric media with their refractive index modulated periodically in time, offer new opportunities in photonics arising from time reflections and momentum bandgaps. Here, we study the emission of light from a radiation source inside a PTC. We solve the general classical and quantum mechanical models of emission in a temporally-varying medium, and find that radiation is always exponentially amplified when associated with the momentum gap, whether initiated by a macroscopic source, an atom, or by vacuum fluctuations, drawing the amplification energy from the modulation. The radiation linewidth becomes narrower as time advances, and is centered in the middle of the momentum gap. We calculate the spontaneous decay rate of an atom embedded in a PTC and show that it vanishes at the band edge due to low density of photonic states. Finally, we propose the concept of nonresonant tunable PTC lasers.
