We study theoretically the deformation of the Fermi surface (FS) of a three-dimensional gas of Rydberg-dressed $^{6}\mathrm{Li}$ atoms. The laser dressing to high-lying Rydberg $D$ states results in angle-dependent soft-core-shaped interactions whose anisotropy is described by multiple spherical harmonics. We show that this can drastically modify the shape of the FS and that its deformation depends on the interplay between the Fermi momentum ${k}_{F}$ and the reciprocal momentum $\overline{k}$ corresponding to the characteristic soft-core radius of the dressing-induced potential. When ${k}_{F}<\overline{k}$ , the dressed interaction stretches a spherical FS into an ellipsoid. When ${k}_{F}\ensuremath{\gtrsim}\overline{k}$, complex deformations are encountered which exhibit multipolar characteristics. We analyze the formation of Cooper pairs around the deformed FS and show that they occupy large orbital angular momentum states ( $p, f$ , and $h$ wave) coherently. Our study demonstrates that Rydberg dressing to high angular momentum states may pave a route toward the investigation of unconventional Fermi gases and multiwave superconductivity.We study theoretically the deformation of the Fermi surface (FS) of a three-dimensional gas of Rydberg-dressed $^{6}\mathrm{Li}$ atoms. The laser dressing to high-lying Rydberg $D$ states results in angle-dependent soft-core-shaped interactions whose anisotropy is described by multiple spherical harmonics. We show that this can drastically modify the shape of the FS and that its deformation depends on the interplay between the Fermi momentum ${k}_{F}$ and the reciprocal momentum $\overline{k}$ corresponding to the characteristic soft-core radius of the dressing-induced potential. When ${k}_{F}<\overline{k}$, the dressed interaction stretches a spherical FS into an ellipsoid. When ${k}_{F}\ensuremath{\gtrsim}\overline{k}$, complex deformations are encountered which exhibit multipolar characteristics. We analyze the formation of Cooper pairs around the deformed FS and show that they occupy large orbital angular momentum states ($p, f$, and $h$ wave) coherently. Our study demonstrates that Rydberg dressing to high angular momentum states may pave a route toward the investigation of unconventional Fermi gases and multiwave superconductivity.

arXiv:2104.10591Physical Review ADec 20, 20214 citations

Novel platforms for quantum simulation using a lithium-6 quantum gas microscope: tweezer arrays and Rydberg-dressed fermions

Zoe Z. Yan, Benjamin M. Spar, Elmer Guardado-Sanchez +1 more

Bulletin of the American Physical SocietyJun 1, 20210 citations

f -wave superfluidity from repulsive interaction in Rydberg-dressed Fermi gas

Ahmet Keleş, Erhai Zhao, Xiaopeng Li

Interacting Fermi gas provides an ideal model system to understand unconventional pairing and intertwined orders relevant to a large class of quantum materials. Rydberg-dressed Fermi gas is a recent experimental system where the sign, strength, and range of the interaction can be controlled. The interaction in momentum space has a negative minimum at ${q}_{c}$ inversely proportional to the characteristic length scale in real space, the soft-core radius ${r}_{c}$ . We show theoretically that single-component (spinless) Rydberg-dressed Fermi gas in two dimensions has a rich phase diagram with superfluid and density wave orders due to the interplay of the Fermi momentum ${p}_{F}$ , interaction range ${r}_{c}$ , and interaction strength ${u}_{0}$ . For repulsive bare interactions ${u}_{0}>0$ , the dominant instability is a $f$ -wave superfluid for ${p}_{F}{r}_{c}\ensuremath{\lesssim}2$ and a density wave for ${p}_{F}{r}_{c}\ensuremath{\gtrsim}4$. The $f$ -wave pairing in this repulsive Fermi gas is reminiscent of the conventional Kohn-Luttinger mechanism but has a much higher ${T}_{c}$ . For attractive bare interactions ${u}_{0}<0$ , the leading instability is $p$ -wave pairing. The phase diagram is obtained from a functional renormalization group that treats all competing many-body instabilities in the particle-particle and particle-hole channels on an equal footing.Interacting Fermi gas provides an ideal model system to understand unconventional pairing and intertwined orders relevant to a large class of quantum materials. Rydberg-dressed Fermi gas is a recent experimental system where the sign, strength, and range of the interaction can be controlled. The interaction in momentum space has a negative minimum at ${q}_{c}$ inversely proportional to the characteristic length scale in real space, the soft-core radius ${r}_{c}$. We show theoretically that single-component (spinless) Rydberg-dressed Fermi gas in two dimensions has a rich phase diagram with superfluid and density wave orders due to the interplay of the Fermi momentum ${p}_{F}$, interaction range ${r}_{c}$, and interaction strength ${u}_{0}$. For repulsive bare interactions ${u}_{0}>0$, the dominant instability is a $f$-wave superfluid for ${p}_{F}{r}_{c}\ensuremath{\lesssim}2$ and a density wave for ${p}_{F}{r}_{c}\ensuremath{\gtrsim}4$. The $f$-wave pairing in this repulsive Fermi gas is reminiscent of the conventional Kohn-Luttinger mechanism but has a much higher ${T}_{c}$. For attractive bare interactions ${u}_{0}<0$, the leading instability is $p$-wave pairing. The phase diagram is obtained from a functional renormalization group that treats all competing many-body instabilities in the particle-particle and particle-hole channels on an equal footing.

arXiv:1906.04235Physical Review AFeb 28, 202012 citations

We study theoretically the deformation of the Fermi surface (FS) of a three-dimensional gas of Rydberg-dressed

^{6}\mathrm{Li}

atoms. The laser dressing to high-lying Rydberg

D

states results in angle-dependent soft-core-shaped interactions whose anisotropy is described by multiple spherical harmonics. We show that this can drastically modify the shape of the FS and that its deformation depends on the interplay between the Fermi momentum

{k}_{F}

and the reciprocal momentum

\overline{k}

corresponding to the characteristic soft-core radius of the dressing-induced potential. When

{k}_{F}<\overline{k}

, the dressed interaction stretches a spherical FS into an ellipsoid. When ${k}_{F}\ensuremath{\gtrsim}\overline{k}$, complex deformations are encountered which exhibit multipolar characteristics. We analyze the formation of Cooper pairs around the deformed FS and show that they occupy large orbital angular momentum states (

p, f

, and

h

wave) coherently. Our study demonstrates that Rydberg dressing to high angular momentum states may pave a route toward the investigation of unconventional Fermi gases and multiwave superconductivity.

{q}_{c}

inversely proportional to the characteristic length scale in real space, the soft-core radius

{r}_{c}

. We show theoretically that single-component (spinless) Rydberg-dressed Fermi gas in two dimensions has a rich phase diagram with superfluid and density wave orders due to the interplay of the Fermi momentum

{p}_{F}

, interaction range

{r}_{c}

, and interaction strength

{u}_{0}

. For repulsive bare interactions

{u}_{0}>0

, the dominant instability is a

f

-wave superfluid for ${p}_{F}{r}_{c}\ensuremath{\lesssim}2$ and a density wave for ${p}_{F}{r}_{c}\ensuremath{\gtrsim}4$. The

f

-wave pairing in this repulsive Fermi gas is reminiscent of the conventional Kohn-Luttinger mechanism but has a much higher

{T}_{c}

. For attractive bare interactions

{u}_{0}<0

, the leading instability is

p

-wave pairing. The phase diagram is obtained from a functional renormalization group that treats all competing many-body instabilities in the particle-particle and particle-hole channels on an equal footing.