Phonon counting thermometry of an ultracoherent membrane resonator near its motional ground state

Ivan Galinskiy; Yeghishe Tsaturyan; Michał Parniak; Eugene S. Polzik

doi:10.1364/optica.390939

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arXiv · 2005.14173

Phonon counting thermometry of an ultracoherent membrane resonator near its motional ground state

Ivan Galinskiy·Yeghishe Tsaturyan·Michał Parniak·Eugene S. Polzik

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Abstract

Generation of non-Gaussian quantum states of macroscopic mechanical objects is key to a number of challenges in quantum information science, ranging from fundamental tests of decoherence to quantum communication and sensing. Heralded generation of single-phonon states of mechanical motion is an attractive way towards this goal, as it is, in principle, not limited by the object size. Here we demonstrate a technique which allows for generation and detection of a quantum state of motion by phonon counting measurements near the ground state of a 1.5 MHz micromechanical oscillator. We detect scattered photons from a membrane-in-the-middle optomechanical system using an ultra-narrowband optical filter, and perform Raman-ratio thermometry and second-order intensity interferometry near the motional ground state ($\bar{n}=0.23\pm0.02$ phonons). With an effective mass in the nanogram range, our system lends itself for studies of long-lived non-Gaussian motional states with some of the heaviest objects to date.

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Ivan Galinskiy, Yeghishe Tsaturyan, Michał Parniak, Eugene S. Polzik. 2020-05-28. Phonon counting thermometry of an ultracoherent membrane resonator near its motional ground state. https://doi.org/10.1364/optica.390939

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