Quantop seminar by Georg Enzian

Online at: https://ucph-ku.zoom.us/j/64273394654


Adding or subtracting a single quantum of excitation to a thermal state of a bosonic system has the counter-intuitive effect of approximately doubling its mean occupation. We perform the first experimental demonstration of this effect outside optics by implementing single-phonon addition and subtraction to a thermal state of a mechanical oscillator via Brillouin optomechanics in an optical whispering-gallery microresonator. Using a detection scheme that combines single-photon counting and optical heterodyne detection, we observe this doubling of the mechanical thermal fluctuations. At the end we will also discuss multi-phonon subtraction and the non-Gaussianity of the prepared states.