Nonlinear optical characteristics of monolayer MoSe2
详细信息 查看全文
- 作者：Chinh Tam Le ; Daniel J. Clark ; Farman Ullah ; Velusamy Senthilkumar ; Joon I. Jang ; Yumin Sim ; Maeng-Je Seong ; Koo-Hyun Chung ; Hyoyeol Park and Yong Soo Kim
- 刊名：Annalen der Physik
- 出版年：2016
- 出版时间：August 2016
- 年：2016
- 卷：528
- 期：7-8
- 页码：551-559
- 全文大小：641K
- ISSN：1521-3889
文摘
In this study, we utilized picosecond pulses from an Nd:YAG laser to investigate the nonlinear optical characteristics of monolayer MoSe2. Two-step growth involving the selenization of pulsed-laser-deposited MoO3 film was employed to yield the MoSe2 monolayer on a SiO2/Si substrate. Raman scattering, photoluminescence (PL) spectroscopy, and atomic force microscopy verified the high optical quality of the monolayer. The second-order susceptibility χ(2) was calculated to be ∼50 pm V−1 at the second harmonic wavelength ∼810 nm, which is near the optical gap of the monolayer. Interestingly, our wavelength-dependent second harmonic scan can identify the bound excitonic states including negatively charged excitons much more efficiently, compared with the PL method at room temperature. Additionally, the MoSe2 monolayer exhibits a strong laser-induced damage threshold ∼16 GW cm−2 under picosecond-pulse excitation. Our findings suggest that monolayer MoSe2 can be considered as a promising candidate for high-power, thin-film-based nonlinear optical devices and applications.