Laser-cooling Cadmium Bosons and Fermions with Near Ultraviolet Triplet Excitations

Abstract

Cadmium is laser-cooled and trapped with excitations to triplet states with UVA light, first using only the 67 kHz wide 326 nm intercombination line and subsequently, for large loading rates, the 25 MHz wide 361 nm 3 P 2 → 3 D 3 transition. Eschewing the hard UV 229 nm 1 S 0 → 1 P 1 transition, only small magnetic fields gradients, less than 6 G cm−1, are required enabling a 100% transfer of atoms from the 361 nm trap to the 326 nm narrow-line trap. All 8 stable cadmium isotopes are straightforwardly trapped, including two nuclear-spin- 1 2 fermions that require no additional repumping. We observe evidence of 3 P 2 collisions limiting the number of trapped metastable atoms, report isotope shifts for 111Cd and 113Cd of the 326 nm 1 S 0 → 3 P 1, 480nm 3 P 1 → 3 S 1, and 361 nm 3 P 2 → 3 D 3 transitions, and measure the 114Cd 5s5p 3 P 2 → 5s5d 3 D 3 transition frequency to be 830 096 573(15) MHz.