Crépel Valentin, Fu Liang
Department of Physics, Massachusetts Institute of Technology, Cambridge, MA 02139.
Proc Natl Acad Sci U S A. 2022 Mar 29;119(13):e2117735119. doi: 10.1073/pnas.2117735119. Epub 2022 Mar 23.
SignificanceWe present a mechanism for unconventional superconductivity in doped band insulators, where short-ranged pairing interaction arises from Coulomb repulsion due to virtual interband or excitonic processes. Remarkably, electron pairing is found upon infinitesimal doping, giving rise to Bose-Einstein condensate (BEC)-Bardeen-Cooper-Schrieffer (BCS) crossover at low density. Our theory explains puzzling behaviors of superconductivity and predicts spin-triplet pairing in electron-doped ZrNCl and WTe.
重要性
我们提出了一种掺杂带绝缘体中非常规超导的机制，其中短程配对相互作用源于由于虚拟带间或激子过程引起的库仑排斥。值得注意的是，在极小的掺杂量下就发现了电子配对，在低密度下产生了玻色-爱因斯坦凝聚（BEC）-巴丁-库珀-施里弗（BCS）交叉。我们的理论解释了超导的令人困惑的行为，并预测了电子掺杂的ZrNCl和WTe中的自旋三重态配对。
