Measurement of complex line shapes by phase-locked cavity ring-down and buildup spectroscopy

Hodges, Joseph T.

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https://hdl.handle.net/2142/107465 Copy

Description

Title

Measurement of complex line shapes by phase-locked cavity ring-down and buildup spectroscopy

Author(s)

Hodges, Joseph T.

Contributor(s)

• Lisak, Daniel
• Gillis, Keith A.
• Ciurylo, Roman
• Cygan, Agata
• Fleisher, Adam J.

Issue Date

2020-06-26

Keyword(s)

• Lineshapes
• Collisional effects

Abstract

Light propagation in a passively decaying optical resonator occurs exclusively at the cavity resonance frequencies because only these fields satisfy the source-free wave equation. This mechanism occurs regardless of the frequency spectrum of the light source. Likewise, after switching on a light source to build up power within a resonator, transient fields at the cavity resonance frequencies are induced which prevent the instantaneous buildup of intra-cavity circulating power. For the case of mode-matched excitation by a single-frequency laser, the transient response of the system involves fields at the incident laser frequency and the cavity resonance frequency. To illustrate, we show that a frequency-agile probe laser which maintains phase lock to an optical resonator during both decay and buildup events yields exponentially damped heterodyne beat signals between the incident laser field and the local cavity resonance. These signals have a damping rate equal to one half the conventional ring-down value and occur at the frequency difference of the source laser and resonance fields. This technique enables the simultaneous measurement of absorption (decay rate) and dispersion (mode shifting) associated with light-matter interaction in a ring-down cavity. We illustrate how these complementary data can be used to measure complex-valued line shapes and validate associated line profiles.

Publisher

International Symposium on Molecular Spectroscopy

Type of Resource

Text

Language

eng

Permalink

http://hdl.handle.net/2142/107465

Copyright and License Information

Copyright 2020 is held by the Author(s)

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