| Texto completo | |
| Autor(es): |
Lind, Alexander J.
;
Kowligy, Abijith
;
Timmers, Henry
;
Cruz, Flavio C.
;
Nader, Nima
;
Silfies, Myles C.
;
Allison, Thomas K.
;
Diddams, Scott A.
Número total de Autores: 8
|
| Tipo de documento: | Artigo Científico |
| Fonte: | Physical Review Letters; v. 124, n. 13, p. 6-pg., 2020-04-01. |
| Resumo | |
The mid-infrared atmospheric window of 3-5.5 mu m holds valuable information regarding molecular composition and function for fundamental and applied spectroscopy. Using a robust, mode-locked fiberlaser source of < U fs pulses in the near infrared, we explore quadratic (chi((2))) nonlinear optical processes leading to frequency comb generation across this entire mid-infrared atmospheric window. With experiments and modeling, we demonstrate intrapulse difference frequency generation that yields few-cycle mid-infrared pulses in a single pass through periodically poled lithium niobate. Harmonic and cascaded chi((2)) nonlinearities further provide direct access to the carrier-envelope offset frequency of the near infrared driving pulse train. The high frequency stability of the mid-infrared frequency comb is exploited for spectroscopy of acetone and carbonyl sulfide with simultaneous bandwidths exceeding 11 THz and with spectral resolution as high as 0.003 cm(-1). The combination of low noise and broad spectral coverage enables detection of trace gases with concentrations in the part-per-billion range. (AU) | |
| Processo FAPESP: | 18/26673-5 - Espectroscopia e Sensoriamento com Pentes de Frequências Ópticas: de DC ao Visível |
| Beneficiário: | Flavio Caldas da Cruz |
| Modalidade de apoio: | Bolsas no Exterior - Pesquisa |