Jay Deep Sau

About

I am a theoretical condensed matter physicist with a broad interest in quantum many-body physics relevant to experiments. Advances in experimental physics have pushed the design of materials and devices towards the regime of quantum many-body physics. At the same time conceptual advances at the boundary of theoretical condensed matter, quantum information and high-energy physics such as topological quantum field theories, entanglement entropy, holography and many-body localization all point to a new era of understanding new quantum mechanical many-body phenomena. I am primarily interested in searching for manifestations of these beautiful ideas in phenomena in the real world.

One such phenomenon, which is at the heart of topological quantum field theory, is topological degeneracy of quantum states. Majorana zero modes in topological superconductors are one of the most exciting examples in this regard, where relatively conventional phases can be used to realize such topologically protected degeneracies that can potentially be used as qubits. In fact, Microsoft is pursuing one such platform based on potential topological superconductivity in semiconductors proximitized by superconductors as a relatively near-term approach to topological quantum computation. I have been involved in predicting strategies and understanding measurements in this field for over a decade. Actually, topological superconductivity provides one of the most interesting applications of topological materials. But each topological material has additional strengths in terms of robustness but possible limitations in terms of the type of accessible devices. Proposing experiments such as RF spectroscopy of line Josephson junctions is another favorite research direction. The pursuit of Majorana zero modes has led to an interest in harnessing semiconductor/superconductor devices more broadly. I am keen to take advantage of this interest and have been thinking about ways to use semiconductor superconductor junctions to trap and control other conventional qubits as well.

Quantum information processing is only the more near-term application of quantum many-body physics. I have been actively following the recent rapid sequence of discoveries in van der Waals heterostructures. These materials have demonstrated a myriad of phases starting from Stoner ferromagnetism to fractional quantum anomalous Hall effect as well as chiral superconductivity. I have been contributing to this effort , mostly in the vicinity of topological superconductivity, but also elsewhere. Topological principles can be used to understand aspects of these materials as well as other quantum materials. In a recent work, I collaborated to develop a description of the chiral anomaly in Weyl semi-metals in the presence of interactions as a t'Hooft anomaly associated with lattice translation symmetry. Other examples of topics that I have found to be interesting include quantum dynamics of fractional quantum Hall point contacts using matrix product state simulations, classical time crystals as well as the interplay of topological defects in spin-orbit coupled ultra-cold atomic gases. Ultimately, my hope is to be able to take advantage of the deluge of efforts in quantum systems combined with the perspectives from quantum many-body physics to make quantum mechanics more intuitive.

Affiliations

Research Interests

People

News

• August 5, 2025

  JQI research news: Researchers report new progress in the Majorana-qubit direction.

• July 14, 2023

  Promoted to Professor of Physics at the University of Maryland.

• February 3, 2016

  Jay Deep Sau receives National Science Foundation CAREER Award.

• February 23, 2016

  Jay Deep Sau receives Sloan Research Fellowship.

Publications

Selected recent publications

• Andreev spin qubits bound to Josephson vortices in spin-orbit coupled planar Josephson junctions, arXiv:2512.11021 [cond-mat.mes-hall] (2025)
• Detection of Majorana zero modes bound to Josephson vortices in planar superconductor–topological insulator–superconductor junctions, Phys. Rev. B 111, 235442 (2025)
• Capacitance-based fermion parity readout and predicted Rabi oscillations in a Majorana nanowire, Phys. Rev. B 111, 224509 (2025)
• Theory for Dissipative Time Crystals in Coupled Parametric Oscillators, Phys. Rev. Lett. 133, 266601 (2024)
• Interaction robustness of the chiral anomaly in Weyl semimetals and Luttinger liquids from a mixed anomaly approach, Phys. Rev. B 113, 075141 (2026)
• Constrained Motions and Slow Dynamics in One-Dimensional Bosons with Double-Well Dispersion, Phys. Rev. Lett. 132, 046001 (2024)
• Eliashberg Theory for Dynamical Screening in Bilayer Exciton Condensation, Phys. Rev. Lett. 133, 056501 – Published 29 July, 2024

ArXiv | Google Scholar

Teaching