SnP 2 S 6 : A Promising Infrared Nonlinear Optical Crystal with Strong Nonresonant Second Harmonic Generation and Phase-Matchability
SnP 2 S 6 : A Promising Infrared Nonlinear Optical Crystal with Strong Nonresonant Second Harmonic Generation and Phase-Matchability
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SnP 2 S 6：一种有前途的红外非线性光学晶体，具有强非谐振二次谐波产生和相位匹配性
DOI：
10.1021/acsphotonics.2c00131
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发表时间：
2022
期刊：
影响因子：
7
通讯作者：
Hautier, Geoffroy
中科院分区：
文献类型：
--
作者：
He, Jingyang;Lee, Seng Huat;Naccarato, Francesco;Brunin, Guillaume;Zu, Rui;Wang, Yuanxi;Miao, Leixin;Wang, Huaiyu;Alem, Nasim;Hautier, Geoffroy
高功率宽带可调谐红外激光系统在光谱学和自由空间通信等领域有着广泛的应用。这些系统需要分别使用和/差频产生的用于波长上/下转换的非线性光学（NLO）晶体。NLO晶体需要满足许多竞争性标准，包括大的非线性光学极化率、大的激光损伤阈值（LIDT）、宽的透明范围和相位匹配性。在这里，我们报告的SnP_2S_6体单晶具有大的非共振二次谐波系数d33 = 53 pm V-1在1550 nm和一个大的LIDT为350 GW cm-2的飞秒激光脉冲。它还表现出从0.54到8.5 μm的宽透明度范围（带隙为2.3 eV），并且可以是I型和II型相位匹配。完整的线性和SHG张量的测量以及预测的第一性原理计算，他们是在极好的协议。电子能带结构中的两个相对平坦的导带被示出为通过非共振光学响应的双共振增强来增强非共振SHG响应。因此，SnP 2S 6是红外激光应用的优秀候选者。
High-power infrared laser systems with broad-band tunability are of great importance due to their wide range of applications in spectroscopy and free-space communications. These systems require nonlinear optical (NLO) crystals for wavelength up/down conversion using sum/difference frequency generation, respectively. NLO crystals need to satisfy many competing criteria, including large nonlinear optical susceptibility, large laser-induced damage threshold (LIDT), wide transparency range, and phase-matchability. Here, we report bulk single crystals of SnP2S6with a large nonresonant SHG coefficient ofd33= 53 pm V–1at 1550 nm and a large LIDT of 350 GW cm–2for femtosecond laser pulses. It also exhibits a broad transparency range from 0.54 to 8.5 μm (bandgap of ∼2.3 eV) and can be both Type I and Type II phase-matched. The complete linear and SHG tensors are measured as well as predicted by first-principles calculations, and they are in excellent agreement. Two relatively flat conduction bands in the electronic band structure are shown to enhance the nonresonant SHG response through a double resonance enhancement of the nonresonant optical response. Therefore, SnP2S6is an outstanding candidate for infrared laser applications.