Infrared-to-THz Detection and Spectroscopy with Whispering-Gallery-Mode Microresonators

Year: 2022

Authors: D’Ambrosio D.; Capezzuto M.; Aiello R.; Delli Santi MG.; Sorgi A.; Malara P.; Avino S.; Giorgini A.; Maddaloni P.; Consolino L.; Vitiello MS.; De Natale P.; Gagliardi G.

Autors Affiliation: Consiglio Nazionale delle Ricerche (CNR); Istituto Nazionale di Ottica (INO-CNR); Consiglio Nazionale delle Ricerche (CNR); Istituto Nanoscienze (NANO-CNR); Consiglio Nazionale delle Ricerche (CNR); Istituto Nazionale di Ottica (INO-CNR)

Abstract: A novel room-temperature photodetector based on a silica-microsphere optical resonator operating from the mid-infrared to the terahertz spectral region is reported. The sensor relies on a free-space visible laser whose frequency is locked to the center of a whispering-gallery mode (WGM). The devised scheme automatically tracks any small change in the microresonator ´ s size and refractive index that occurs upon illumination with radiation absorbed by silica. In this way, direct detection of quantum-cascade laser beams around 4.3 and 111 mu m wavelengths is shown, down to minimum noise-equivalent power levels of approximate to 1 pW root Hz(-1) with a dynamic range > 100 dB. The microsphere resonator is then exploited, for the first time, as a photodetector in absorption spectroscopy of the (CO2)-C-12 fundamental ro-vibrational band and of very-weak (CH3OH)-C-13 rotational lines.

Journal/Review: ADVANCED PHOTONICS RESEARCH

Volume: 3 (12)      Pages from: 2200147-1  to: 2200147-6

More Information: The experimental work and Davide D’Ambrosio’s fellowship were funded by the Italian Ministry for University & Research (MUR) in the framework of the PRIN2017 ’PELM’ project (20177PSCKT grant). M.S.V. acknowledges the financial support from the European Research Council, SPRINT (681379). Also, we acknowledge funding from the CNR project TEROCODE.
KeyWords: infrared detection; molecular spectroscopy; optical microresonator; THz detection; whispering-gallery mode
DOI: 10.1002/adpr.202200147

Citations: 1
data from “WEB OF SCIENCE” (of Thomson Reuters) are update at: 2024-11-17
References taken from IsiWeb of Knowledge: (subscribers only)
Connecting to view paper tab on IsiWeb: Click here
Connecting to view citations from IsiWeb: Click here