All-optical short pulse translation through cross-phase modulation in a VO_2 thin film

Abstract

VO2 is a promising material for reconfigurable photonic devices due to the ultrafast changes in electronic and optical properties associated with its dielectric-to-metal phase transition. Based on a fiber-optic, pump-probe setup at 1550 nm wavelength window, and by varying the pump-pulse duration, we show that the material phase transition is primarily caused by the pump-pulse energy. For the first time, we demonstrate that the instantaneous optical phase modulation of probe during pump leading edge can be utilized to create short optical pulses at probe wavelength, through optical frequency discrimination. This circumvents the impact of long recovery time well known for the phase transition of VO2.

Large Scale Synthesis of Nanopyramidal-Like VO2 Films by an Oxygen-Assisted Etching Growth Method with Significantly Enhanced Field Emission Properties

“…Upon the MIPT, the crystalline structure changes from a high-symmetry tetragonal rutile phase (P4 2 /mnm, R phase) to a lower symmetry monoclinic phase (P2 1 /c, M 1 phase) with dimerized V–V pairs exhibiting alternating zig-zag like chains [4,5]. Noticeable physical property changes such as optical transmittance [7,8,9], electrical conductivity [10,11], permittivity [12,13], and magnetic susceptibility [14,15] can be observed, making these kind of materials potentially suitable for a great many stimuli-responsive devices, e.g., ultrafast optical switches [16,17], sensing devices [18,19], next-generation terahertz transistors [20], non-Boolean computing materials [21], uncooled infrared bolometer [22,23], and other novel concepts of switching devices [24,25,26,27,28].…”