论文标题
飞秒激光照射薄薄$ t_d $ -mote $ _2 $获得的持续光生成状态
Persistent photogenerated state attained by femtosecond laser irradiation of thin $T_d$-MoTe$_2$
论文作者
论文摘要
激光激发已成为暴露物质隐藏状态并按需促进相过渡的一种手段。由于空间和/或时间操纵的光的传递，这种激光诱导的转换通常会导致，从而将能量量子载在热背景以上。在这里，我们报告了时间分辨的宽带飞秒（FS）瞬时吸收测量值对Weyl Semimetal候选薄片$ t_d $ -mote $ _2 $，受到FS-PhotoExcitation的各种水平和方案。我们的结果表明，冲动的FS-LASER辐照改变了低温$ T_D $相位的层间行为，这证明了其特征连贯的$^1 $ a $ _1 $ _1 $ _1 $ 13 cm $^$ 13 cm $^{ - 1} $ shear Phonon模式的持续消失。我们发现，这种结构转换可承受高达500 K的热退火，尽管可以通过FS-LASER在室温下将其恢复为1 $ t $ \'阶段。我们的工作为拓扑特性的可逆光学控制打开了大门。
Laser excitation has emerged as a means to expose hidden states of matter and promote phase transitions on demand. Such laser induced transformations are often rendered possible owing to the delivery of spatially and/or temporally manipulated light, carrying energy quanta well above the thermal background. Here, we report time-resolved broadband femtosecond (fs) transient absorption measurements on thin flakes of Weyl semimetal candidate $T_d$-MoTe$_2$ subjected to various levels and schemes of fs-photoexcitation. Our results reveal that impulsive fs-laser irradiation alters the interlayer behavior of the low temperature $T_d$ phase as evidenced by the persistent disappearance of its characteristic coherent $^1$A$_1$ $=$ 13 cm$^{-1}$ shear phonon mode. We found that this structural transformation withstands thermal annealing up to 500 K, although it can be reverted to the 1$T$\' phase by fs-laser treatment at room temperature. Our work opens the door to reversible optical control of topological properties.
