Inhomogeneous mechanical losses in micro-oscillators with high reflectivity coating
Authors: Serra E., Cataliotti F. S., Marin F., Marino F., Pontin A., Prodi G. A., Bonaldi M.
Autors Affiliation: Interdisciplinary Laboratory for Computational Science (LISC), FBK-University of Trento, I-38123 Povo (TN), Italy; Istituto Nazionale di Fisica Nucleare (INFN), Gruppo Collegato di Trento, I-38123 Povo (TN), Italy; Dipartimento di Energetica, Universita` di Firenze, Via Santa Marta 3, I-50139 Firenze, Italy; European Laboratory for Non-Linear Spectroscopy (LENS), Via Carrara 1, I-50019 Sesto Fiorentino (FI), Italy; INFN, Sezione di Firenze, Via Sansone 1, I-50019 Sesto Fiorentino (FI), Italy; Dipartimento di Fisica, Universita` di Firenze, Via Sansone 1, I-50019 Sesto Fiorentino (FI), Italy; CNR-ISC, Via Madonna del Piano 10, I-50019 Sesto Fiorentino (FI), Italy; Dipartimento di Fisica, Universita` di Trento, I-38123 Povo (TN), Italy; Institute of Materials for Electronics and Magnetism, Nanoscience-Trento-FBK Division, I-38123 Povo (TN), Italy
Abstract: We characterize the mechanical quality factor of micro-oscillators covered by a highly reflective coating. We test an approach to the reduction of mechanical losses that consists in limiting the size of the coated area to reduce the strain and the consequent energy loss in this highly dissipative component. Moreover, a mechanical isolation stage is incorporated in the device. The results are discussed on the basis of an analysis of homogeneous and non-homogeneous losses in the device and validated by a set of finite-element models. The contributions of thermoelastic dissipation and coating losses are separated and the measured quality factors are found in agreement with the calculated values, while the absence of unmodeled losses confirms that the isolation element integrated in the device efficiently uncouples the dynamics of the mirror from the support system. Also the resonant frequencies evaluated by finite-element models are in good agreement with the experimental data, and allow the estimation of the Young modulus of the coating. The models that we have developed and validated are important for the design of oscillating micro-mirrors with high quality factor and, consequently, low thermal noise. Such devices are useful in general for high sensitivity sensors, and in particular for experiments of quantum opto-mechanics. (C) 2012 American Institute of Physics. [http://dx.doi.org/10.1063/1.4728217]
Journal/Review: JOURNAL OF APPLIED PHYSICS
Volume: 111 (11) Pages from: 113109 to: 113109
KeyWords: Micro-mirrors; Optical Coatings; OptomechanicsDOI: 10.1063/1.4728217Citations: 11data from “WEB OF SCIENCE” (of Thomson Reuters) are update at: 2021-08-01References taken from IsiWeb of Knowledge: (subscribers only)Connecting to view paper tab on IsiWeb: Click hereConnecting to view citations from IsiWeb: Click here