Rare-earth doped optical dimers

The optical forces applied to a rare-earth doped optical dimer made of identical Yb3+:YAG nanospheres placed in the plane electromagnetic field propagating in vacuum has been theoretically considered. The electromagnetic fields at wavelengths 968 nm and 1030 nm have been normally and axially directed to the dimer axis. Wavelengths 968 nm and 1030 nm are resonant with the electron transitions of the Yb3+ ions and can generate the Stokes and anti-Stokes cycles, respectively. It has been shown that the electromagnetic field propagating at wavelength 1030 nm not only can be used to control optical forces applied to the dimer, but can cause cooling of the dimer, which is desirable in a number of applications.