• 文献标题:   Isospin magnetism and spin-polarized superconductivity in Bernal bilayer graphene
  • 文献类型:   Article
  • 作  者:   ZHOU HX, HOLLEIS L, SAITO Y, COHEN L, HUYNH W, PATTERSON CL, YANG FY, TANIGUCHI T, WATANABE K, YOUNG AF
  • 作者关键词:  
  • 出版物名称:   SCIENCE
  • ISSN:   0036-8075 EI 1095-9203
  • 通讯作者地址:  
  • 被引频次:   53
  • DOI:   10.1126/science.abm8386
  • 出版年:   2022

▎ 摘  要

In conventional superconductors, Cooper pairing occurs between electrons of opposite spin. We observe spin-polarized superconductivity in Bernal bilayer graphene when doped to a saddle-point van Hove singularity generated by a large applied perpendicular electric field. We observe a cascade of electrostatic gate-tuned transitions between electronic phases distinguished by their polarization within the isospin space defined by the combination of the spin and momentum-space valley degrees of freedom. Although all of these phases are metallic at zero magnetic field, we observe a transition to a superconducting state at finite magnetic field B-parallel to approximate to 150 milliteslas applied parallel to the two-dimensional sheet. Superconductivity occurs near a symmetry-breaking transition and exists exclusively above the B-parallel to limit expected of a paramagnetic superconductor with the observed transition critical temperature T-C approximate to 30 millikelvins, consistent with a spin-triplet order parameter.