Orbital-dependent dimensional crossover of a -wave Feshbach resonance
Phys. Rev. A 114, 023329 – Published 31 August, 2026
DOI: https://doi.org/10.1103/vt5d-xsrq
Abstract
We report the observation of a dimensional crossover of a -wave Feshbach resonance in an ultracold, spin-polarized Fermi gas confined by a one-dimensional optical lattice. Using high-resolution atom-loss spectroscopy, we resolve the orbital doublet associated with the and scattering channels over a wide range of lattice depths. In the weak-confinement regime, the atom loss signal associated with the branch is stronger, consistent with the twofold orbital degeneracy of the three-dimensional system. As the lattice confinement increases, the relative loss weight of the two orbital branches evolves continuously toward the quasi-two-dimensional limit, indicating a progressive suppression of relative motion along the lattice direction. In addition, we observe a systematic confinement dependence of the orbital splitting between the two resonance branches. These results provide an experimental characterization of orbital-dependent -wave scattering in reduced dimensions and motivate future microscopic studies of confined anisotropic scattering.