Detection of a Levitated Nanoparticle’s Position via Self-Homodyne

The efficiency with which the position of a levitated nanoparticle is detected is one factor that sets the minimum temperature of the particle’s center-of-mass motion that can be achieved by feedback cooling. Typically, the detection is based on the interference of the light scattered by the particle with a reference Gaussian beam in a homodyne setup [1] - [3] . This detection scheme is limited by the wavefront mismatch between the scattered and...