Simultaneous nonlinear wavelength and mode conversion for high-brightness blue sources
Abstract
We investigate frequency doubling of focused Bessel-like higher order fiber modes in a one-dimensionally quasi-phase matched structured KTP crystal. A single higher-order fiber mode, L P 0 , 7 , was generated at 971 nm using a fiber optical parametric amplifier pumped by sub-nanosecond pulses at 1064 nm. Frequency doubling to 485.5 nm was achieved with a maximum conversion efficiency of 48%, which produced a highly structured blue beam without any brightness improvement with respect to the fundamental beam. By optimizing the phase mismatch, we also experimentally demonstrate clean on-axis conversion—resulting from cascaded χ ( 2 ) : χ ( 2 ) processes, which is in good agreement with our numerical simulations, that give rise to brightness enhancement.
Document Details
- Document Type
- Pub Defense Publication
- Publication Date
- Nov 01, 2021
- Source ID
- 10.1364/josab.436188
Entities
People
- Andrius Zukauskas
- Robert Lindberg
- Siddharth Ramachandran
- Valdas Pasiskevicius
- Xiao Liu
Organizations
- Boston University
- Office of Naval Research
- Office of Naval Research Global
- Royal Institute of Technology