Two-body relaxation of spin-polarized fermions in reduced dimensionalities near a p -wave Feshbach resonance

Abstract

We study inelastic two-body relaxation in a spin-polarized ultracold Fermi gas in the presence of a p-wave Feshbach resonance. It is shown that in reduced dimensionalities, especially in the quasione-dimensional case, the enhancement of the inelastic rate constant on approach to the resonance is strongly suppressed compared to three dimensions. This may open promising paths for obtaining novel many-body states.

Two-body relaxation in a Fermi gas at a p -wave Feshbach resonance

“…Similar to Ref. [22], we included the imaginary part to the inverse of the scattering volume as 1/V = 1/V + i/V 1 , where V 1 > 0 and is assumed to be independent of the external magnetic field [22]. The inelastic loss rate constant can be expressed as β(E) = v r × σ(E), where v r = 2 k/m is the relative velocity between two atoms of mass m and σ(E) is the p-wave inelastic scattering cross section for the relative energy E = mv 2 r /4.…”

“…Our findings support the prediction of the loss suppression in 2D and we experimentally observed an even higher suppression than that predicted theoretically. Since further suppression of the dipolar loss in one dimension has been discussed theoretically [22], confining the atoms in one dimension may provide the way to achieve p-wave superfluid in cold atom systems. The elastic collisional properties of the atoms in the low dimension as well as the inelastic collisional properties studied in the current work are also important toward realization of p-wave superfluid.…”

“…The inelastic loss rate constant can be expressed as β(E) = v r × σ(E), where v r = 2 k/m is the relative velocity between two atoms of mass m and σ(E) is the p-wave inelastic scattering cross section for the relative energy E = mv 2 r /4. Using the Smatrix element notation [22], σ(E) can be written as…”

“…The dipolar losses can be elucidated by including the imaginary part to the inverse scattering volume in the two-body scattering amplitude [21,22]. The imaginary scattering volume quantifies the measure of the efficiency of dipolar relaxation losses.…”

Many-body stabilization of a resonant p -wave Fermi gas in one dimension

“…In the regime 1/l → 0 + , k j has an imaginary part scaling as l −1/2 and we find it can be expanded as k j = k + ic j l −1/2 − d j l −1 , where {c j } and {d j } satisfy the same sets of equations as (13,14). Therefore the energy correction up to the order of 1/l has a unified form for different sides of resonance, i.e., ∆E = (−1/l) j (c 2 j + 2kd j ).…”