Josephson Junction and Qubit Devices Based on Epitaxial Nitride Superconductor/Semiconductor
Abstract
This project aims to develop high performance Josephson junctions and qubits using epitaxial nitride superconductors. The specific goals are two-fold: 1) To fabricate MBE all-nitride Josephson Junctions; 2) To investigate new physics and application spaces enabled by the epitaxial junctions.In the past three years, with support provided by ONR, the Yale group collaborated with D. Jena s team at Cornell on the development of nitride-based superconductor/semiconductor devices. With devices patterned from single layer films (NbN or TiN), we show clear advantages of epitaxial superconductors compared to non-epitaxial materials. Using trilayer junction wafers grown by the Cornell team, we have developed a reliable process to fabricate all-epitaxial Josephson junctions. In this funding period, we will optimize our growth processes and device designs to accommodate larger barrier thickness and achieve desired junction performances. After successful demonstration of all-nitride Josephson junctions (NJJ), we will explore their applications in superconducting quantum circuits, including superconducting qubits based on NJJs and benchmark their performance compared to Al-based devices in terms of qubit lifetime (T1) and quantum coherences (T2). Another application area is NJJ-based quantum amplifiers. Such devices provide much larger nonlinearity than our current kinetic inductance amplifier fabricated from single layer NbN films thereforeshould lead to broader bandwidth and higher power handling.Approved for public release.
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- Jan 12, 2023
- Source ID
- N000142312121
Entities
People
- Ai-Hong Tang
Organizations
- Office of Naval Research
- United States Navy
- Yale University