Nonlinear optics with high power few-cycle Erbium fiber frequency combs (Dr. Daniel Lesko)

(in-person)
Datum: 17.06.2022
Uhrzeit: 14:00
Vortragende(r): Dr. Daniel Lesko
Time and Frequency Division, NIST & Department of Chemistry & Physics, University of Colorado
Ort: Max Planck Institute of Quantum Optics
Raum: Herbert Walther Lecture Hall

Erbium fiber (Er:fiber) frequency combs have been a critical technology for basic and applied researchsuch as optical clocks, distance measurements, low-noise microwave generation, astronomical spectrographcalibration, and spectroscopy. Furthermore, for spectroscopic applications, a secondary phase-locked combcan be used to down-convert the optical absorption information on one comb into the radio frequencydomain providing comb-mode optical resolution with high signal to noise at fast acquisition rates. Whilethese Er:fiber combs have benefited from commercially available ultralow-noise mode-locked laser oscillators,versatile dispersion-engineered and nonlinear fibers, as well as an inexpensive, fiber-integrated off-the-shelfcomponent catalogue, most strong molecular signatures do not overlap with Erbium emission limiting thespectroscopic applications.

This motivates the need to develop low-noise and high peak power combs to
take advantage of strong χ(2) optical nonlinearities in materials to efficiently shift the spectrum to different
spectroscopic regions. In this talk I demonstrate a scalable source of watt scale near-single-cycle pulses from
robust and low-noise erbium fibre (Er:fibre) technology. With this MW-scale peak power, <10 fs, comb I
show multi-octave coverage from the ultraviolet to the far infrared with a resolving power of 1010 across 1
PHz of bandwidth. I discuss novel applications of this light source from the infrared, where we can generate
spectral brightness and bandwidth rivalling a synchrotron, to the ultraviolet, where we can perform carrier
envelope phase metrology to elucidate non-perturbative dynamics in solid state semiconductors. Finally
I will provide an outlook for the development of ultra-broadband ultraviolet and visible combs using this
scalable short pulse generation with Er:fiber combs. Link