Veillette Martin Y, Sheehy Daniel E, Radzihovsky Leo, Gurarie Victor
Department of Physics, University of Colorado, Boulder, Colorado 80309, USA.
Phys Rev Lett. 2006 Dec 22;97(25):250401. doi: 10.1103/PhysRevLett.97.250401. Epub 2006 Dec 19.
We study a rotating atomic Fermi gas near a narrow s-wave Feshbach resonance in a uniaxial trap with frequencies Omega perpendicular, Omega z. We predict the upper-critical angular velocity, omega c2(delta,T), as a function of temperature T and detuning delta across the BEC-BCS crossover. The suppression of superfluidity at omega c2 is distinct in the BCS and BEC regimes, with the former controlled by depairing and the latter by the dilution of bosonic molecules. At low T and Omega z << Omega perpendicular, in the BCS and crossover regimes of 0 less similar delta less similar delta c, omega c2 is implicitly given by [formula: see text], vanishing as omega c2 approximately Omega perpendicular(1 - delta/delta c)(1/2) near [formula: see text] (with Delta the BCS gap and gamma the resonance width), and extending the bulk result variant Planck's over 2pi omega c2 approximately 2Delta2/epsilonF to a trap. In the BEC regime of delta < 0 we find omega c2-->Omega perpendicular-, where molecular superfluidity is destroyed only by large quantum fluctuations associated with comparable boson and vortex densities.
我们研究了在具有垂直频率Ω⊥和轴向频率Ωz的单轴阱中，靠近窄s波费什巴赫共振的旋转原子费米气体。我们预测了上临界角速度ωc2(δ,T)，它是温度T和失谐量δ在玻色-爱因斯坦凝聚-玻色-爱因斯坦凝聚超流转变过程中的函数。在ωc2处超流性的抑制在玻色-爱因斯坦凝聚和玻色-爱因斯坦凝聚超流转变区域是不同的，前者由配对破坏控制，后者由玻色子分子的稀释控制。在低温且Ωz << Ω⊥时，在0≤δ≤δc的玻色-爱因斯坦凝聚和转变区域，ωc2由[公式：见原文]隐式给出，在[公式：见原文]附近ωc2趋近于0，即ωc2≈Ω⊥(1 - δ/δc)(1/2)（其中Δ是玻色-爱因斯坦凝聚能隙，γ是共振宽度），并将体材料结果ħ/2πωc2≈2Δ2/εF扩展到了阱的情况。在δ < 0的玻色-爱因斯坦凝聚区域，我们发现ωc2→Ω⊥，此时分子超流性仅被与可比玻色子和涡旋密度相关的大量子涨落破坏。
