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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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This content will become publicly available on December 1, 2025
The nature of non-phononic excitations in disordered systems
Abstract The frequency scaling exponent of low-frequency excitations in microscopically small glasses, which do not allow for the existence of waves (phonons), has been in the focus of the recent literature. The density of statesg(ω) of these modes obeys anωsscaling, where the exponents, ranging between 2 and 5, depends on the quenching protocol. The orgin of these findings remains controversal. Here we show, using heterogeneous-elasticity theory, that in a marginally-stable glass sampleg(ω) follows a Debye-like scaling (s= 2), and the associated excitations (type-I) are of random-matrix type. Further, using a generalisation of the theory, we demonstrate that in more stable samples, other, (type-II) excitations prevail, which are non-irrotational oscillations, associated with local frozen-in stresses. The corresponding frequency scaling exponentsis governed by the statistics of small values of the stresses and, therefore, depends on the details of the interaction potential.
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- Award ID(s):
- 2154241
- PAR ID:
- 10503017
- Publisher / Repository:
- Springer Nature
- Date Published:
- Journal Name:
- Nature Communications
- Volume:
- 15
- Issue:
- 1
- ISSN:
- 2041-1723
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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