Agenda

Abstract : Silicon carbide nanowires are exquisite force sensors with both high  sensitivity and vectorial force mapping capabilities. The sensitivity of these nanowires, their sub-wavelength  dimensions  and  their  strong  interaction  with  light,  provides important  coupling  strength  when  inserted  in  a  small  volume  fibered  optical cavity.  This  is  an  ideal  configuration  to  finely  study  the  two  facets  of  the optomechanical interaction. In this talk we will present how we evaluate the large optomechanical coupling strength of our system as well as the optical force applied on the nanowire using  a  response  measurement  setup.  In  particular,  we  will stress  the  high  force sensitivity down to a single photon modulation [1].  In the prospect of conducting this experiment at very low temperature, we  also developed an optomechanical platform in a dilution fridge. We will present the first  results  demonstrating  the  measurements  of  the  thermal  motion  of  a  SiC nanowire thermalized at 30 milli Kelvin [2].  

[1] F. Fogliano et al, Mapping the cavity optomechanical interaction with sub-wavelength-
sized ultrasensitive nanomechanical force sensors, PRX 11, 021009 (2021)
[2] F. Fogliano et al, Ultrasensitive nano-optomechanical force sensor operated at dilution
temperatures. Nature Communications 12, 4124 (2021)