Adaptive non-collinear autocorrelation of few-cycle pulses with an angular tunable bi-mirror

Abstract

Adaptive autocorrelation with an angular tunable micro-electro-mechanical system is reported. A piezo-actuated Fresnel bi-mirror structure was applied to measure the second order autocorrelation of near-infrared few-cycle laser pulses in a non-collinear setup at tunable superposition angles. Because of enabling measurements with variable scaling and minimizing the influence of distortions by adaptive self-reconstruction, the approach extends the capability of autocorrelators. Flexible scaling and robustness against localized amplitude obscurations are demonstrated. The adaptive reconstruction of temporal frequency information by the Fourier analysis of autocorrelation data is shown. Experimental results and numerical simulations of the beam propagation and interference are compared for variable angles.

Toward On-Chip MEMS-Based Optical Autocorrelator

“…It is worth mentioning that the autocorrelation signal, defined by (3) or (4), is ideally an even function of regardless of the symmetry of the actual pulse. Furthermore, the ratio between the maximum value and the background level for the interferometric and intensity autocorrelation signals is 8 to 1 and 3 to 1, respectively [11].…”

“…Another technique that requires high spatial coherence for few-cycle pulses measurement using an angular tunable bi-mirror for noncollinear autocorrelation is reported in ref. [11].…”

High-Flexibility Control of Structured Light with Combined Adaptive Optical Systems

“…As an application of combined SLM and Fresnel bi-mirror (configuration Com 1), we studied the possibility to improve the quality of non-collinear autocorrelation of few-cycle pulses. The principle of adaptive non-collinear autocorrelation with flexible Fresnel bi-mirrors was previously published by some of the authors [52]. Arrangement and signal analysis are described in this reference.…”

“…Diffraction at the edges can mostly be eliminated. Information about second-order field autocorrelation can be derived from averaged horizontal cuts through the intensity profiles [52].…”

Micro Fresnel mirror array with individual mirror control

“…Fresnel mirrors can, for example, be used to fabricate linear optical gratings directly into the photoresist without the use of a photomask [3]. It was shown that an adaptive Fresnel mirror can be used in adaptive pulse autocorrelation [4], and for direct nano-machining of subwavelength structures on silicon or dielectric substrates by laser-induced periodic surface structures (LIPSS) [5,6]. LIPSS are formed by the interference of incident and scattered light pulses on the surface of the material [7].…”