Open AccessHighly efficient THG in TiO_2 nanolayers for third-order pulse characterization
Author(s) -
Susanta Kumar Das,
Christoph Schwanke,
Andreas Pfuch,
W. Seeber,
Martin Böck,
Günter Steinmeyer,
Thomas Elsaesser,
R. Grünwald
Publication year - 2011
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.19.016985
Subject(s) - materials science , femtosecond , optics , laser , nanocrystalline material , characterization (materials science) , optoelectronics , thin film , interferometry , nonlinear optics , nanotechnology , physics
Third harmonic generation (THG) of femtosecond laser pulses in sputtered nanocrystalline TiO2 thin films is investigated. Using layers of graded thickness, the dependence of THG on the film parameters is studied. The maximum THG signal is observed at a thickness of 180 nm. The corresponding conversion efficiency is 26 times larger compared to THG at the air-glass interface. For a demonstration of the capabilities of such a highly nonlinear material for pulse characterization, third-order autocorrelation and interferometric frequency-resolved optical gating (IFROG) traces are recorded with unamplified nanojoule pulses directly from a broadband femtosecond laser oscillator.