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Title: A simple method for characterizing and engineering thermal relaxation of an optical microcavity

Abstract

Thermal properties of a photonic resonator are determined not only by intrinsic properties of materials, such as thermo-optic coefficient, but also by the geometry and structure of the resonator. Techniques for characterization and measurement of thermal properties of individual photonic resonator will benefit numerous applications. In this work, we demonstrate a method to optically measure the thermal relaxation time and effective thermal conductance of a whispering gallery mode microcavity using optothermal effect. Two nearby optical modes within the cavity are optically probed, which allows us to quantify the thermal relaxation process of the cavity by analyzing changes in the transmission spectra induced by optothermal effect. We show that the effective thermal conductance can be experimentally deduced from the thermal relaxation measurement, and it can be tailored by changing the geometric parameters of the cavity. The experimental observations are in good agreement with the proposed analytical modeling. This method can be applied to various resonators in different forms.

Authors:
; ; ; ;  [1]
  1. Department of Electrical and Systems Engineering, Washington University, St. Louis, Missouri 63130 (United States)
Publication Date:
OSTI Identifier:
22594336
Resource Type:
Journal Article
Resource Relation:
Journal Name: Applied Physics Letters; Journal Volume: 109; Journal Issue: 6; Other Information: (c) 2016 Author(s); Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; GEOMETRY; OPTICAL MODES; PROBES; RELAXATION TIME; RESONATORS; SIMULATION; SPECTRA; THERMODYNAMIC PROPERTIES

Citation Formats

Chen, Weijian, Zhu, Jiangang, Özdemir, Şahin Kaya, Peng, Bo, and Yang, Lan, E-mail: yang@ese.wustl.edu. A simple method for characterizing and engineering thermal relaxation of an optical microcavity. United States: N. p., 2016. Web. doi:10.1063/1.4960665.
Chen, Weijian, Zhu, Jiangang, Özdemir, Şahin Kaya, Peng, Bo, & Yang, Lan, E-mail: yang@ese.wustl.edu. A simple method for characterizing and engineering thermal relaxation of an optical microcavity. United States. doi:10.1063/1.4960665.
Chen, Weijian, Zhu, Jiangang, Özdemir, Şahin Kaya, Peng, Bo, and Yang, Lan, E-mail: yang@ese.wustl.edu. Mon . "A simple method for characterizing and engineering thermal relaxation of an optical microcavity". United States. doi:10.1063/1.4960665.
@article{osti_22594336,
title = {A simple method for characterizing and engineering thermal relaxation of an optical microcavity},
author = {Chen, Weijian and Zhu, Jiangang and Özdemir, Şahin Kaya and Peng, Bo and Yang, Lan, E-mail: yang@ese.wustl.edu},
abstractNote = {Thermal properties of a photonic resonator are determined not only by intrinsic properties of materials, such as thermo-optic coefficient, but also by the geometry and structure of the resonator. Techniques for characterization and measurement of thermal properties of individual photonic resonator will benefit numerous applications. In this work, we demonstrate a method to optically measure the thermal relaxation time and effective thermal conductance of a whispering gallery mode microcavity using optothermal effect. Two nearby optical modes within the cavity are optically probed, which allows us to quantify the thermal relaxation process of the cavity by analyzing changes in the transmission spectra induced by optothermal effect. We show that the effective thermal conductance can be experimentally deduced from the thermal relaxation measurement, and it can be tailored by changing the geometric parameters of the cavity. The experimental observations are in good agreement with the proposed analytical modeling. This method can be applied to various resonators in different forms.},
doi = {10.1063/1.4960665},
journal = {Applied Physics Letters},
number = 6,
volume = 109,
place = {United States},
year = {Mon Aug 08 00:00:00 EDT 2016},
month = {Mon Aug 08 00:00:00 EDT 2016}
}
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