2008/03/31 by A. Vinante, Andrea Vinante, M. Bignotto +15 · 76 citations
Engineering · Physics and Astronomy · #Amplifier #Bar (unit) #Electrical engineering #Geophysics and Sensor Technology #Ground state #Interference (communication) #Mechanical and Optical Resonators #Optoelectronics #Physics #Pulsars and Gravitational Waves Research #Quantum #Quantum interference #Quantum mechanics #Resonator #Squid #Thermodynamics #Water cooling #quant-ph
paper · pdf · doi:10.1103/physrevlett.101.033601
published in Physical Review Letters 101(3), 033601 (American Physical Society) · 4 pages, 4 figures
openalex publication_date 2008/07/14 · arxiv created 2008/09/18 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
We apply a feedback cooling technique to simultaneously cool the three electromechanical normal modes of the ton-scale resonant-bar gravitational wave detector AURIGA. The measuring system is based on a dc superconducting quantum interference device (SQUID) amplifier, and the feedback cooling is applied electronically to the input circuit of the SQUID. Starting from a bath temperature of 4.2 K, we achieve a minimum temperature of 0.17 mK for the coolest normal mode. The same technique, implemented in a dedicated experiment at subkelvin bath temperature and with a quantum limited SQUID, could allow to approach the quantum ground state of a kilogram-scale mechanical resonator.