Charge-$4e$ superconductivity as a novel phase of matter remains elusive so far. Here, we show that charge-4e phase can arise as a vestigial order above the nematic superconducting transition temperature in time-reversal-invariant nematic superconductors. On the one hand, the nontrivial topological defect—nematic vortex—is energetically favored over the superconducting phase vortex when the nematic stiffness is less than the superfluid stiffness; consequently the charge-$4e$ phase emerges by proliferation of nematic vortices upon increasing temperatures. On the other hand, the Ginzburg-Landau theory of the nematic superconductors has two distinct decoupling channels to either charge-$4e$ orders or nematic orders; by analyzing the competition between the effective mass of the charge-$4e$ order and the cubic potential of the nematic order, we find a sizable regime where the charge-$4e$ order is favored. These two analyses consistently show that nematic superconductors can provide a promising route to realize charge-$4e$ phases, which may apply to candidate nematic superconductors such as ${\mathrm{PbTaSe}}_2$ and twisted bilayer graphene.

中文翻译：

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二维和三维向列超导体的 Charge-4e 超导性

收费-$4\mathrm{电子}$到目前为止，超导性作为一种新的物质相仍然难以捉摸。在这里，我们表明，在时间反转不变的向列超导体中，电荷 4e 相可以作为向列超导转变温度以上的残余有序出现。一方面，当向列刚度小于超流体刚度时，非平凡的拓扑缺陷——向列涡旋比超导相涡旋在能量上更有优势；因此，收费 -$4\mathrm{电子}$随着温度的升高，向列涡旋的扩散会出现相。另一方面，向列超导体的 Ginzburg-Landau 理论有两个不同的去耦通道，可以通过$4\mathrm{电子}$订单或向列订单；通过分析电荷的有效质量之间的竞争——$4\mathrm{电子}$ 顺序和向列顺序的立方势，我们发现了一个相当大的制度，其中电荷 -$4\mathrm{电子}$订单优先。这两项分析一致表明，向列超导体可以提供一条有前途的途径来实现电荷-$4\mathrm{电子}$ 相，这可能适用于候选向列超导体，例如 ${\mathrm{硒化铅}}_2$ 和扭曲的双层石墨烯。