Evanescent straight tapered-fiber coupling of ultra-high Q optomechanical micro-resonators in a low-vibration helium-4 exchange-gas cryostat

Abstract

We developed an apparatus to couple a 50-micrometer diameter whispering-gallery silica microtoroidal resonator in a helium-4 cryostat using a straight optical tapered-fiber at 1550nm wavelength. On a top-loading probe specifically adapted for increased mechanical stability, we use a specifically-developed "cryotaper" to optically probe the cavity, allowing thus to record the calibrated mechanical spectrum of the optomechanical system at low temperatures. We then demonstrate excellent thermalization of a 63-MHz mechanical mode of a toroidal resonator down to the cryostat's base temperature of 1.65K, thereby proving the viability of the cryogenic refrigeration via heat conduction through static low-pressure exchange gas. In the context of optomechanics, we therefore provide a versatile and powerful tool with state-of-the-art performances in optical coupling efficiency, mechanical stability and cryogenic cooling.

8 pages, 6 figures

References in corpus (10)

• Laser cooling of a nanomechanical oscillator into its quantum ground state
• Sideband Cooling Micromechanical Motion to the Quantum Ground State
• Optomechanically induced transparency
• Quantum-coherent coupling of a mechanical oscillator to an optical cavity mode
• Cavity Optomechanics
• Quantum Optomechanics - throwing a glance
• High-sensitivity optical monitoring of a micro-mechanical resonator with a quantum-limited optomechanical sensor
• Optomechanical coupling in a two-dimensional photonic crystal defect cavity
• Optomechanical sideband cooling of a micromechanical oscillator close to the quantum ground state
• Optical fiber taper coupling and high-resolution wavelength tuning of microdisk resonators at cryogenic temperatures

Cited by in corpus (10)

• Heralded single phonon preparation, storage and readout in cavity optomechanics
• Laser cooling and control of excitations in superfluid helium
• Ultra-low-loss tapered optical fibers with minimal lengths
• Near-field integration of a SiN nanobeam and a SiO${}_2$ microcavity for Heisenberg-limited displacement sensing
• Phonon Quantum Nondemolition Measurements in Nonlinearly Coupled Optomechanical Cavities
• Cryogenic and hermetically sealed packaging of photonic chips for optomechanics
• Optomechanics and thermometry of cryogenic silica microresonators
• Optical microscope and tapered fiber coupling apparatus for a dilution refrigerator
• Remote Macroscopic Entanglement on a Photonic Crystal Architecture
• Waveguide-loaded silica fibers for coupling to high-index micro-resonators