SO（5）不变自旋3/2费米气体模型的精确解

Fermi Surface Resonance and Quantum Criticality in Strongly Interacting Fermi Gases

Fermions in the Fermi gas obey the Pauli exclusion principle restricting any two fermions from filling the same quantum state. Strong interaction between fermions can completely change the properties of the Fermi gas. In our theoretical study we find a new exotic quantum phase in strongly interacting Fermi gases constrained to a certain condition imposed on the Fermi surfaces which we call the Fermi surface resonance. The new phase is quantum critical which can be identified by the power-law frequency tail of the spectral density and divergent static susceptibilities. An especially striking fe…

再论二维费米气体

Two-dimensional Fermi Gas Revisited

一些作者对具有短程排斥相互作用（当然也包括自旋）的二维费米子气体不能被一致地视为重整化准粒子系统的证明提出了异议。本文表明，在这些文件中的一些参数是无效的或无关的。

弱耦合费米气体的动量分布

Momentum Distribution of a Weakly Coupled Fermi Gas

本文应用Sea-boson方法计算了具有短程排斥作用的二维无自旋连续费米气体的动量分布。我们发现系统的基态是朗道费米液体（$ 0 < Z_{F} < 1 $）。我们也将这种方法应用于研究一维系统中长程规范相互作用的情况。我们绘制了这个系统的维格纳晶体相。

Non-Fermi liquid fixed point for an imbalanced gas of fermions in $1+ε$ dimensions

We consider a gas of two species of fermions with population imbalance. Using the renormalization group in $d=1+ε$ dimensions, we show that for spinless fermions and $ε> 0$ a fixed point appears at finite attractive coupling where the quasiparticle residue vanishes, and identify this with the transition to Larkin--Ovchinnikov--Fulde--Ferrell order (inhomogeneous superconductivity). When the two species of fermions also carry spin degrees of freedom we find a fixed point indicating a transition to spin density wave order.

A Composite Fermion Approach to the Ultracold Dilute Fermi Gas

It is argued that the recently observed Fermi liquids in strongly interacting ultracold Fermi gases are adiabatically connected to a projected Fermi gas. This conclusion is reached by constructing a set of Jastrow wavefunctions, following Tan's observations on the structure of the physical Hilbert space [Annals of Physics 323, 2952 (2008)]. The Jastrow projection merely implements the Bethe-Peierls condition on the BCS and Fermi gas wavefunctions. This procedure provides a simple picture of the emergence of Fermi polarons as composite fermions in the normal state of the highly polarized gas. I…

Communal pairing in spin-imbalanced Fermi gases

A spin-imbalanced Fermi gas with an attractive contact interaction forms a superconducting state whose underlying components are superpositions of Cooper pairs that share minority-spin fermions. This superconducting state includes correlations between all available fermions, making it energetically favorable to the Fulde--Ferrell--Larkin--Ovchinnikov superconducting state. The ratio of the number of up- and down-spin fermions in the instability is set by the ratio of the up- and down-spin density of states in momentum at the Fermi surfaces, to fully utilize the accessible fermions. We present …