Optical super-resolution effect induced by nonlinear characteristics of graphene oxide films

• 来源期刊: 光电子快报（英文版）
• 年，卷（期）: 2018,（1）
• 页码范围: 21-24
• 页数: 4页
• 语种: 英文
• DOI: 10.1007/s11801-018-7163-5

摘要

In this work,we focus on the optical super-resolution effect induced by strong nonlinear saturation absorption (NSA) of graphene oxide (GO) membranes.The third-order optical nonlinearities are characterized by the canonical Z-scan technique under femtosecond laser (wavelength:800 nm,pulse width:100 fs) excitation.Through controlling the applied femtosecond laser energy,NSA of the GO films can be tuned continuously.The GO film is placed at the focal plane as a unique amplitude filter to improve the resolution of the focused field.A multi-layer system model is proposed to present the generation of a deep sub-wavelength spot associated with the nonlinearity of GO films.Moreover,the parameter conditions to achieve the best resolution (～λ6) are determined entirely.The demonstrated results here are useful for high density optical recoding and storage,nanolithography,and super-resolution optical imaging.