论文标题
在窄带材料中生成相干的声子波：扭曲的双层石墨烯移动器
Generating coherent phonon waves in narrow-band materials: a twisted bilayer graphene phaser
论文作者
论文摘要
扭曲的双层石墨烯（TBG）的电子速度极低，声音速度超过费米速度。该机制使使用TBG通过刺激的发射来扩大晶格的振动波，遵循自由电子激光器的相同操作原理。我们的工作提出了一种依靠慢电子带来产生一致的声音子束的激光机制。我们提出了一个基于TBG中的波动电子的设备，我们将其配对移相器。该设备在Terahertz（THZ）频率范围内生成声子梁，然后可以将其用于产生THZ电磁辐射。在固体中生成相干声子的能力在控制量子记忆，探测量子状态，实现物质的非平衡阶段以及设计新型THZ光学设备方面打破了新的基础。
Twisted bilayer graphene (TBG) exhibits extremely low Fermi velocities for electrons, with the speed of sound surpassing the Fermi velocity. This regime enables the use of TBG for amplifying vibrational waves of the lattice through stimulated emission, following the same principles of operation of free-electron lasers. Our work proposes a lasing mechanism relying on the slow-electron bands to produce a coherent beam of acoustic phonons. We propose a device based on undulated electrons in TBG, which we dub the phaser. The device generates phonon beams in a terahertz (THz) frequency range, which can then be used to produce THz electromagnetic radiation. The ability to generate coherent phonons in solids breaks new ground in controlling quantum memories, probing quantum states, realizing non-equilibrium phases of matter, and designing new types of THz optical devices.
