Investigation of the possibility of ultra-deep laser cooling using a quadrupole transition

Abstract

We consider the kinetics of atoms in nonuniform spatially polarised light fields resonant to the quadrupole optical transition with F g → F e = F g + 2 (F g,e is the total angular momentum in the ground and excited states). The lowest possible temperatures of laser cooling of atoms are analysed numerically and the results are compared with the data obtained for sub-Doppler cooling using light waves resonant to electric dipole optical transitions.

Systematic study of tunable laser cooling for trapped-ion experiments

“…with K (d) (h) being the dipole pattern for the decay and η i are the Lamb-Dicke parameters for the corresponding dipole transitions (i = 2, 3 in figure 1(a)). For the quadrupole transition the relaxation operator has a similar form to (A.3) with replacement of the dipole with the quadrupole pattern for the decay K (q) (h) and corresponding Lamb-Dicke parameter η 1 [54].…”