title: Threshold Dependence of Deep- and Near-subwavelength Ripples Formation on Natural MoS2 Induced by Femtosecond Laser.
abstract: Deep sub-wavelength ripples (DSRs) and near sub-wavelength ripples (NSRs) with uniform periods of ~160 nm and ~660 nm generated at the MoS2-vacuum interface is reported for the first time by the processing of femtosecond laser (800 nm, 120 fs, 1 kHz) in this paper. The DSRs and NSRs formation fluence thresholds are experimentally determined as 160 mJ/cm(2) and 192 mJ/cm(2), respectively. In addition, the ripple period is insensitive to the pulse number. Moreover, Raman analyses show that the MoS2 lattice in the irradiated area does not exhibit oxidation at room environment and the crystalline representation is well preserved in NSRs region. We attribute our result to the joint interactions of the spallation and sublimation of layered MoS2 together with the laser induced surface plasmon polaritons and propose an explanation to the threshold dependence of the ripple period. Our study provides some insights for ultrafast laser-matter interactions and indicates a simple effective method for future nano-fabrication of MoS2.
authors.affiliation: The MOE Key Laboratory of Weak Light Nonlinear Photonics, TEDA Applied Physics Institute and School of Physics, Nankai University, Tianjin 300457, China.
authors.forename: Yusong
authors.initials: Y
authors.lastname: Pan
authors.affiliation: The MOE Key Laboratory of Weak Light Nonlinear Photonics, TEDA Applied Physics Institute and School of Physics, Nankai University, Tianjin 300457, China.|The Institute of Photoelectronic Thin Film Devices and Technology, Nankai University, Tianjin 300071, China.
authors.forename: Ming
authors.initials: M
authors.lastname: Yang
authors.affiliation: The MOE Key Laboratory of Weak Light Nonlinear Photonics, TEDA Applied Physics Institute and School of Physics, Nankai University, Tianjin 300457, China.
authors.forename: Yumei
authors.initials: Y
authors.lastname: Li
authors.affiliation: The MOE Key Laboratory of Weak Light Nonlinear Photonics, TEDA Applied Physics Institute and School of Physics, Nankai University, Tianjin 300457, China.
authors.forename: Zhenhua
authors.initials: Z
authors.lastname: Wang
authors.affiliation: The MOE Key Laboratory of Weak Light Nonlinear Photonics, TEDA Applied Physics Institute and School of Physics, Nankai University, Tianjin 300457, China.
authors.forename: Chunling
authors.initials: C
authors.lastname: Zhang
authors.affiliation: The Institute of Photoelectronic Thin Film Devices and Technology, Nankai University, Tianjin 300071, China.
authors.forename: Ying
authors.initials: Y
authors.lastname: Zhao
authors.affiliation: The MOE Key Laboratory of Weak Light Nonlinear Photonics, TEDA Applied Physics Institute and School of Physics, Nankai University, Tianjin 300457, China.
authors.forename: Jianghong
authors.initials: J
authors.lastname: Yao
authors.affiliation: The MOE Key Laboratory of Weak Light Nonlinear Photonics, TEDA Applied Physics Institute and School of Physics, Nankai University, Tianjin 300457, China.
authors.forename: Qiang
authors.initials: Q
authors.lastname: Wu
authors.affiliation: The MOE Key Laboratory of Weak Light Nonlinear Photonics, TEDA Applied Physics Institute and School of Physics, Nankai University, Tianjin 300457, China.
authors.forename: Jingjun
authors.initials: J
authors.lastname: Xu