论文标题
NICO2O4和多壁碳纳米管的混合纳米结构的非线性光学限制
Nonlinear Optical Limiting with Hybrid Nanostructures of NiCo2O4 and Multiwall Carbon Nanotubes
论文作者
论文摘要
在反向饱和吸收（RSA）方面，非线性光学（NLO）响应已被广泛利用用于光学限制。在这里，我们在实验上证明了NICO2O4和多壁碳纳米管（NCO@MWCNT）的花样杂交纳米结构（NCO@MWCNT）在吸收方面表现出很强的非线性，特别是激发态吸收（ESA）诱导的RSA，当暴露于Nansosecond Laseruse时，它诱导了RSA。我们在混合NCO@MWCNT中获得了强非线性吸收系数（\ b {eta}）和非线性折射率（N2），与单独的NCO或MWCNT相比，分别高2倍和2个数量级的值。这提供了光学限制（fol）和光学发作（FON）阈值CA的光学限制的直接应用。比基准NLO材料低2-10倍，例如石墨烯，2-D转型金属二甲构基化元素（TMDC）材料，并且最近建立了NCO。值得注意的是，对于飞秒泵，NCO@MWCNT的NLO响应由可饱和吸收（SA）主导，分别来自MWCNT和NCO产生的两个光子吸收（TPA）一周。得益于从MWCNT到NCO的电荷传输，N2获得了显着的符号逆转以及更大的振幅。
Nonlinear optical (NLO) response in terms of reverse saturable absorption (RSA) has been exploited extensively for optical limiting. Here, we experimentally demonstrate that flower-like hybrid nanostructures of NiCo2O4 and Multiwall Carbon Nanotubes (NCO@MWCNT) exhibit a strong non-linearity in their absorption, specifically an excited state absorption (ESA) induced RSA, when exposed to nanosecond laser pulses. We obtain strong nonlinear absorption coefficient (\b{eta}) and nonlinear refractive index (n2) in hybrid NCO@MWCNT, the values that are 2-times and 2-orders of magnitude higher, respectively compared to NCO or MWCNT alone. This offers straightforward application in optical limiting with optical limiting (FOL) and optical onset (FON) threshold ca. 2-10 times lower than benchmark NLO materials, e.g., graphene, family of 2-D transition metal dichalcogenides (TMDC) materials and recently established NCO. Notably, for femtosecond pumping, NLO response of NCO@MWCNT is dominated by saturable absorption (SA) with a week contribution from two photon absorption (TPA), arising respectively from MWCNT and NCO. A remarkable sign reversal along with a larger amplitude is obtained for n2 thanks to the charge transfer from MWCNT to NCO.
