论文标题
库仑气体的双极超导性
Bipolaronic superconductivity out of a Coulomb gas
论文作者
论文摘要
我们采用无偏的符号量子蒙特卡洛（Monte Carlo），使用粘结声音调节的电子跳跃模型研究了远程库仑力对双极龙的BEC的影响。在没有远距离排斥的情况下，该模型最近被证明会引起小尺寸的轻质双二颗粒，从而在临界温度$ T_ \ MATHRM {C} $的高值下进行超氟。我们发现，即使远程库仑排斥力仍然比Holstein Bipolarons大得多，我们的模型中的$ T_ \ Mathrm {C} $仍然大得多，并且可以按照Migdal-Eliashberan和McMmillan oftimations of Phonon介导的$ T_ \ Mathrm {C Mathrm {C} $的典型上限的顺序大。我们的工作指出了在低密度状态下的物理简单机制，该机制可能与当前有关稀稀稀型超导体实验有关的实验。
Employing unbiased sign-problem-free quantum Monte Carlo, we investigate the effects of long-range Coulomb forces on BEC of bipolarons using a model of bond phonon-modulated electron hopping. In absence of long-range repulsion, this model was recently shown to give rise to small-size, light-mass bipolarons that undergo a superfluid transition at high values of the critical transition temperature $T_\mathrm{c}$. We find that $T_\mathrm{c}$ in our model even with the long-range Coulomb repulsion remains much larger than that of Holstein bipolarons, and can be on the order of or greater than the typical upper bounds on phonon-mediated $T_\mathrm{c}$ based on the Migdal-Eliashberg and McMillan approximations. Our work points to a physically simple mechanism for superconductivity in the low-density regime that may be relevant to current experiments on dilute superconductors.
