Nanomechanical resonators

The 2012 lecture set out to explain the basic concepts underlying the measurement and control of collective variables in mechanical resonators, by coupling them to a microwave (electromechanical) or optical (optomechanical) field. He has synthesized three possible approaches to handling mechanical degree-of-freedom cooling : 1) feedback control by a " " environment measuring " the mechanical position and producing a corrective force, 2) semi-classical input-output formalism, which had already been outlined for amplifiers in previous lectures and which treats cooling as linear scattering between modes (splitter plate), 3) fully quantum theory of cooling by strong irradiation at the red sideband frequency of the field-resonator coupled mode. The cooling of nanomechanical oscillators is an out-of-equilibrium process that shares many similarities with that of nuclear dynamic polarization and cold atom preparation. The lecture focused on the similarities and differences between these different types of cooling.