Using an optical probe along with single photon detection we have performed effective phonon counting measurements of the acoustic emission and absorption processes in a nanomechanical resonator. Applying these measurements in a Hanbury Brown and Twiss set-up, phonon correlations of the nanomechanical resonator are explored from below to above threshold of a parametric instability leading to self-oscillation of the resonator. Discussion of the results in terms of a "phonon laser", and analysis of the sensitivity of the phonon counting technique are presented.
@article{arxiv.1410.1047,
title = {Phonon counting and intensity interferometry of a nanomechanical resonator},
author = {Justin D. Cohen and Sean M. Meenehan and Gregory S. MacCabe and Simon Groblacher and Amir H. Safavi-Naeini and Francesco Marsili and Matthew D. Shaw and Oskar Painter},
journal= {arXiv preprint arXiv:1410.1047},
year = {2015}
}