Saturated absorption of different layered Bi2Se3 films in the resonance zone

被引：41

作者：

Zhang, Jun ^{[1
]}

Jiang, Tian ^{[1
]}

Zhou, Tong ^{[2
]}

Ouyang, Hao ^{[1
]}

Zhang, Chenxi ^{[1
]}

Xin, Zheng ^{[3
]}

Wang, Zhenyu ^{[3
]}

Chen, Xiang'ai ^{[1
]}

机构：

[1] Natl Univ Def Technol, Coll Adv Interdisciplinary Studies, Changsha 410073, Hunan, Peoples R China

[2] Natl Univ Def Technol, State Key Lab High Performance Comp, Coll Comp, Changsha 410073, Hunan, Peoples R China

[3] Acad Mil Sci PLA China, Natl Inst Def Technol Innovat, Beijing 100010, Peoples R China

来源：

PHOTONICS RESEARCH | 2018年 / 6卷 / 10期

基金：

中国国家自然科学基金;

关键词：

LARGE OPTICAL NONLINEARITY; 2-PHOTON ABSORPTION; TOPOLOGICAL INSULATOR; MOS2; NANOSHEETS; ABSORBERS; BI2TE3; WS2;

D O I：

10.1364/PRJ.6.0000C8

中图分类号：

O43 [光学];

学科分类号：

070207 ; 0803 ;

摘要：

Here, we used the micro P-scan method to investigate the saturated absorption (SA) of different layered Bi2Se3 continuous films. Through resonance excitation, first, we studied the influence of the second surface state (SS) on SA. The second SS resonance excitation (similar to 2.07 eV) resulted in a free carrier cross section that was 4 orders of magnitude larger than usual. At the same time, we found that the fast relaxation process of the massless Dirac electrons is much shorter than that of electrons in bulk states. Moreover, the second SS excitation resonance reduced the saturation intensity. Second, we studied the effect of the thickness on the SA properties of materials. The results showed that the saturation intensity was positively correlated to the thickness, the same as the modulation depth, and the thicker the Bi2Se3 film was, the less the second SS would influence it. This work demonstrated that by using Bi2Se3 as a saturable absorber through changing the thickness or excitation wavelength, a controllable SA could be achieved. (C) 2018 Chinese Laser Press

引用

页码：C8 / C14

页数：7

共 28 条

[1] Large optical nonlinearity of nanoantennas coupled to an epsilon-near-zero material [J].