Frequency-resolved optical gating for characterization of VUV pulses using ultrafast plasma mirror switching

Abstract

We propose and experimentally demonstrate a method for characterizing vacuum ultraviolet (VUV) pulses based on time-resolved reflection spectroscopy of fused silica pumped by an intense laser pulse. Plasma mirror reflection is used as an ultrafast optical switch, which enables us to measure frequency-resolved optical gating (FROG) traces. The VUV temporal waveform can be retrieved from the measured FROG trace using principal component generalized projections algorithm with modification. The temporal profile of the plasma mirror reflectivity is also extracted simultaneously.

Plasma-mirror frequency-resolved optical gating for simultaneous retrieval of a chirped vacuum-ultraviolet waveform and time-dependent reflectivity

“…Details of the experimental setup used in this study are described elsewhere [18] . Briefly, a VUV pulse with nm is obtained through fifth-order harmonic generation using an output pulse from a Ti:sapphire chirped pulse amplification system (795 nm, 60 fs FWHM, 10 Hz, 10 mJ/pulse).…”

“…After the plasma-mirror FROG measurement, a microscopic image of the FS surface is taken and shows the formation of clean elliptical craters. The size of each crater is 33 m high and 60 m wide [18] . Since the diffraction limit of the focal spot size is proportional to the wavelength, the focal spot of the VUV pulses on the FS surface is expected to be smaller than the crater size.…”

Damage-controlled high power lasers and plasma mirror application

“…We have developed a new method named PM-FROG, plasma mirror FROG (frequency-resolved optical gating), to measure the time-dependent intensity and phase of ultrashort-duration vuv pulses [11]. Plasma mirror is useful in this application since the plasma is reflective even to vuv radiation, whereas transparent optical materials required for vuv pulse characterization with other methods are not easily available in this short wavelength region.…”

Design and characterization simulation of Ti: Sapphire‐based femtosecond laser system using Lab2 tools in the NI LabVIEW

“…Such laser can also employ for the generation of coherent X‐rays with a pulse duration of 100 attoseconds . The various diagnostic techniques are used to investigate and characterize the femtosecond laser pulses; these techniques include autocorrelation, frequency‐resolved optical gating (FROG) and spectral phase interferometry for dielectric electric field reconstruction . There is few commercially available software (http://www.swampoptics.com/frog-code.html; http://www.laserquantum.com; http://www.lighttrans.com/; https://www.rp-photonics.com/ultrafast_lasers.html) which are used in femtosecond laser system design, in contrast, Lab2 is free, easier to use and more versatile especially for conventional femtosecond laser system study and design.…”