1.9 μm Few-Cycle Pulses Based on Multi-Thin-Plate Spectral Broadening and Nonlinear Self-Compression

Beijie Shao,Yuxin Leng,Ruxin Li,Junyu Qian,Wenkai Li,Yanyan Li,Yujie Peng

doi:10.1109/jphot.2021.3073541

Abstract

In attosecond and strong-field physics, the acquisition of few-cycle laser sources open up a new area. We report a nonlinear pulse compression technology combining multi-thin-plate spectral broadening and nonlinear self-compression that generates a 0.52 mJ, good spatial quality characteristics and a spectral bandwidth supporting a 14 fs Fourier transform limited duration at 1 kHz repetition rate and at a center wavelength of 1.9 μm. The total energy transfer efficiency is up to 83%. Pulse to pulse stability of the energy output is 0.7% (RMS). The pulse duration is near 3 optical cycles. This pulse compression approach can be a key-enabling technology for the next generation of extreme photonics, attosecond research and coherent x ray-science, and it also can be further extended to mid-infrared lasers with longer wavelengths and higher peak power.

Highlights

With the breakthrough in few-cycle pulse generation, ultra-intense ultrashort lasers help people to explore and understand the interaction between laser and matter
Several robust and popular schemes of the spectral broadening and pulse compression have been proposed to compress the pulse duration to few optical cycles, such as gas-filled hollow core fibers (HCFs) [6, 7], gas-filled multi-pass cells [8,9,10], filamentation [11, 12], and bulk materials [13,14,15,16]
Bulk materials cannot withstand high-power pulses input, so several μJlevel supercontinuum generation (SCG) is generally obtained. This is mainly because the propagating process of high-power laser in the bulk materials is extremely prone to self-focusing effects

Summary

Introduction

With the breakthrough in few-cycle pulse generation, ultra-intense ultrashort lasers help people to explore and understand the interaction between laser and matter. While for bulk materials compression, the development of solid-state nonlinear supercontinuum generation (SCG) has been very rapid especially in the last decade. Bulk materials cannot withstand high-power pulses input, so several μJlevel SCG is generally obtained. This is mainly because the propagating process of high-power laser in the bulk materials is extremely prone to self-focusing effects. A new approach that replacing the bulk materials with multi-thin plates can control and suppress the self-focusing effect inside the medium, which is extremely meaningful [18, 19]. The multi-thin-plate system takes advantage of the nonlinear interaction between the laser and the solid medium for spectral broadening and avoids the self-focusing effect that occurs in the medium and breaks it at the same time

Methods

Results

Conclusion