Optical levitation in high vacuum

Optical levitation of highly transparent particles has been observed in the high-vacuum regime where viscous damping and thermal conductivity are small, the particle is cooled only by thermal radiation, and radiometric forces are negligible. The effects of an impulse and adiabatic manipulation on the dynamics of a sphere were studied from atmospheric pressure down to ∼10−6 Torr. The calculated time for an oscillating particle to decay to half-amplitude due to the intrinsic optical damping at zero pressure is ∼0.7 years.