EAGER: BRAIDING: Collaborative Research: Manipulation of Majorana Modes in Topological Crystalline Insulator Nanowires

University Of Maryland, College Park, College Park MD

Investigators

Abstract

Non-technical Abstract: The team aims to make topological superconducting nanowires as the building blocks of new quantum computers that are more robust and energy efficient than current quantum computers. Nanodevices based on these nanowires are used to demonstrate the basic rules for quantum computations. The superconducting nanowires are made of indium doped tin telluride, and are expected to alleviate some of the challenging technical constraints imposed on a competing system, a semiconducting nanowire with large spin orbit coupling. A portion of the research is included in the undergraduate and graduate physics curriculum to inspire and encourage students to pursue research. Undergraduate students are involved in the project through senior research projects, REU programs, and summer research internships. Collaboration between Yale University and the University of Maryland at College Park provide broader networking opportunities to graduate students. Technical Abstract: The team aims to demonstrate braiding anyon world lines using indium-doped tin telluride (SnTe) topological superconductor nanowires and nanowire junctions. Indium-doped SnTe - SnTe junction nanowires are synthesized via a growth method that adapts the vapor-liquid-solid growth mechanism. Superconducting topological nanowires eliminate the need for superconducting contacts. Nanodevices using the heterojunction nanowires are be fabricated to demonstrate the signatures of Majorana fermions (MFs) at the junctions and perform fusion and braiding operations. A half quantum flux magnetic field is to be applied parallel to the nanowire to ensure the topological superconducting phase while small additional local magnetic fields are to be used to generate, manipulate, and fuse MFs. Quantum dot devices on the nanowire are used to read out the parity through the parity-to-charge conversion. The use of magnetic fields, instead of electric gating, combined with relaxed conditions for the placement of chemical potentials, represents technical advantages for this system.