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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 nm3P2→3D3transition. Eschewing the hard UV 229 nm1S0→1P1transition, 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- fermions that require no additional repumping. We observe evidence of3P2collisions limiting the number of trapped metastable atoms, report isotope shifts for111Cd and113Cd of the 326 nm1S0→3P1, 480nm3P1→3S1, and 361 nm3P2→3D3transitions, and measure the114Cd 5s5p3P2→ 5s5d3D3transition frequency to be 830 096 573(15) MHz.
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Isotope shifts in cadmium as a sensitive probe for physics beyond the standard model
Abstract Isotope shifts (ISs) of atomic energy levels are sensitive probes of nuclear structure and new physics beyond the standard model. We present an analysis of the ISs of the cadmium atom (Cd I) and singly charged cadmium ion (Cd II). ISs of the 229 nm, 326 nm, 361 nm and 480 nm lines of Cd I are measured with a variety of techniques; buffer–gas-cooled beam spectroscopy, capturing atoms in a magneto-optic-trap, and optical pumping. IS constants for the D1and D2lines of Cd II are calculated with high accuracy by employing analytical response relativistic coupled-cluster theory in the singles, doubles and triples approximations. Combining the calculations for Cd II with experiments, we infer IS constants for all low-lying transitions in Cd I. We benchmark existing calculations via different many-body methods against these constants. Our calculations for Cd II enable nuclear charge radii of Cd isotopes to be extracted with unprecedented accuracy. The combination of our precise calculations and measurements shows that King plots for Cd I can improve the state-of-the-art sensitivity to a new heavy boson by up to two orders of magnitude.
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- Award ID(s):
- 2012117
- PAR ID:
- 10388467
- Publisher / Repository:
- IOP Publishing
- Date Published:
- Journal Name:
- New Journal of Physics
- Volume:
- 24
- Issue:
- 12
- ISSN:
- 1367-2630
- Page Range / eLocation ID:
- Article No. 123040
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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