Low-threshold supercontinuum generation in polycrystalline media
Abstract
Until recently, the generation of super-octave continua in bulk materials at full repetition rates of femtosecond (fs) oscillators has been limited to a few special cases of Kerr lens mode-locked Ti:sapphire lasers. In 2019, we described a 3.4-octave fs source with 50 nJ pulse energy at the repetition rate of 78 MHz based on polycrystalline Cr:ZnS [Vasilyev et al., Optica 6, 126 (2019)OPTIC82334-253610.1364/OPTICA.6.000126]. Here we explain the mechanism of fs supercontinuum generation in transition-metal doped polycrystalline II-VI semiconductors at relatively low (nJ-level) pulse energy. We demonstrate that this new supercontinuum regime is enabled by a complex, yet well-reproducible, interplay between the effects arising from the third-order nonlinearity, the quadratic nonlinearities, and thermal optical effects in the medium. We also demonstrate the control of fs pulse propagation in disordered χ ( 2 ) media via the control of the material microstructure.
Document Details
- Document Type
- Pub Defense Publication
- Publication Date
- Apr 21, 2021
- Source ID
- 10.1364/josab.417485
Entities
People
- Igor Moskalev
- Jeremy Peppers
- Jiahui Gu
- Mike Mirov
- Miroslav Kolesik
- Sergey Mirov
- Sergey Vasilyev
- Valentin Gapontsev
- Viktor Smolski
- Yury Barnakov
Organizations
- Air Force Office of Scientific Research
- IPG Photonics
- National Institute of Environmental Health Sciences
- United States Army Research Laboratory
- United States Department of Energy
- University of Alabama at Birmingham
- University of Arizona