Séminaire informel DQMP - Vibrational dynamics in the quantum regime

30.11.2018 15:00 – 16:00

The recent rise of the field of cavity quantum optomechanics is driven by the prospect of manipulating mechanical oscillators in the quantum regime. These oscillators can become new building blocks for quantum technologies, such as quantum coherent frequency converters, quantum memories or quantum-enhanced sensors. In this seminar, I will present proof-of-concept experiments carried out on vibrational modes deep in the quantum regime. My group focuses on high-frequency (>10 THz) vibrational modes, that are ubiquitously found in crystals and molecules, to reach the quantum-noise dominated regime at room-temperature (the phonon energy is much larger than temperature.

In a first part, I will present how pulsed Raman scattering combined with the measurement-induced non-linearity implemented by single photon counting can be used to prepare non-classical vibrational states with sub-Poissonian phonon number statistics [1,2], using the bulk phonon mode of diamond in a room-temperature experiment.

In a second part, I will describe our efforts to build plasmonic nanocavities coupled to Raman-active molecular vibrational modes as a realization of an optomechanical cavity in a regime of negligible thermal occupancy of the mechanical mode [3]. Fabrication steps and first measurements of phonon sideband thermometry will be presented, where the effect of dynamical backaction noise should become observable [4].

[1] Anderson M. et al. Phys. Rev. Lett. 120, 233601 (2018)
[2] Tarrago Velez S. et al., https://arxiv.org/abs/1811.03038
[3] Roelli P. et al. Nature Nanotechnology 11, 164–169 (2016)
[4] Benz F. et al. Science 354, 726-729 (2016)

Lieu

Bâtiment: Ecole de Physique

Salle MaNEP

entrée libre