Open AccessTime-stretched real-time measurement technique for ultrafast absorption variations with TS/s sampling-rate
Author(s) -
Stefan Weber,
Erik H. Waller,
Christoph Kaiser,
Georg von Freymann
Publication year - 2017
Publication title -
optics express
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.25.014125
Subject(s) - ultrashort pulse , picosecond , optics , materials science , resonator , sampling (signal processing) , absorption (acoustics) , saturable absorption , semiconductor , laser , optoelectronics , physics , fiber laser , detector
We present a real-time measurement technique, based on time-stretching for measuring the temporal dynamic of ultrafast absorption variations with a sampling-rate of up to 1.1 TS/s. The single-shot captured data are stretched in a resonator-based time-stretch system with a variable stretch-factor of up to 13.8. The time-window of the time-stretch system for capturing the signal of interest is about 800 ps with an update-rate of 10 MHz. An adapted optical backpropagation algorithm is introduced for reconstructing the original unstretched event. As proof-of-principle the temporal characteristic of a picosecond semiconductor saturable absorber mirror is measured: The real-time results agree well with the results of a conventional pump-probe experiment. The time-stretch technique potentially allows to gain access to a large field of ultrafast absorption variations like semiconductor charge carrier dynamics, irreversible polymerization processes, and saturable absorber materials.