Open AccessOpen-aperture Z-scan study for absorption saturation: accurate measurement of saturation intensity in YLF:Yb for optical refrigeration
Author(s) -
Azzurra Volpi,
Jackson Kock,
Alexander R. Albrecht,
Markus P. Hehlen,
Richard I. Epstein,
Mansoor SheikBahae
Publication year - 2021
Publication title -
optics letters/optics index
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.524
H-Index - 272
eISSN - 1071-2763
pISSN - 0146-9592
DOI - 10.1364/ol.419551
Subject(s) - saturation (graph theory) , analytical chemistry (journal) , materials science , chemistry , mathematics , chromatography , combinatorics
Knowledge of saturation intensity of gain or absorption plays a fundamental role in a variety of applications ranging from lasers to many nonlinear optical processes. Here, we present an analytical expression for open-aperture Z-scan transmission for accurately measuring the saturation intensity in the low absorbance samples but at arbitrary pump intensities. We exploit this formalism to investigate the absorption saturation of L i Y F 4 : Y b 3+ (YLF:Yb) in the anti-Stokes excitation region for optical refrigeration at high pump intensities. An absorption saturation intensity of 14.5±1 k W / c m 2 was measured in YLF:Yb at 1020 nm ( E || c ) at room temperature.