Altermagnetic Routes to Majorana Modes in Zero Net Magnetization

We propose heterostructures that realize first and second order topological superconductivity with vanishing net magnetization by utilizing altermagnetism. Such platforms may offer a significant improvement over conventional platforms with uniform magnetization since the latter suppresses the superconducting gap. We first introduce a 1D semiconductor-superconductor structure in proximity to an altermagnet that realizes end Majorana zero modes (MZMs) with vanishing net magnetization. Additionally, a coexisting Zeeman term provides a tuning knob to distinguish topological and trivial zero modes. We then propose 2D altermagnetic platforms that can realize chiral Majorana fermions or higher order corner MZMs. Our…

• NS
  National Science Foundation
• UD
  U.S. Department of Energy
• SF
  Simons Foundation
• OO
  Office of Science
• KI
  Kavli Institute for Theoretical Physics, University of California, Santa Barbara
• BE
  Basic Energy Sciences

  Award: DE-SC0021238
• AF
  Air Force Office of Scientific Research

  Award: FA9550-20-1-0260
• EF
  Energy Frontier Research Centers