Speaker: Alex Matos Abiague, Wayne State University

Title: Topological Superconductivity in Planar Josephson Junctions

Abstract:

Topological superconductivity (TS) is a phase of matter supporting the formation of quasiparticles called Majorana bound states, which can store information nonlocally and are therefore ideal candidates for building robust qubits with potential applications in fault-tolerant quantum computing [1]. Planar Josephson junctions (JJs) have recently emerged as promising platforms for realizing and manipulating the TS state [2]. However, despite the recent progress, important questions regarding the properties, signatures, and detection of TS remain open. In this talk, I will discuss the relevance and limitations of recent experimental results and propose new effects (e.g., magneto [3] and crystalline [4] anisotropies) that can provide complementary signatures of the transition into the TS state and be used as control knobs for optimizing the topological protection of Majorana bound states. Our theoretical predictions indicate that quantities like critical current [2], spin susceptibility [5], and/or magneto current-phase relation, can be used to map the topological phase diagram, providing a more complete picture of the TS state. I will also discuss recently proposed platforms for realizing, manipulating, and detecting topological qubits in planar JJs [6].

[1] C. Nayak, S. H. Simon, A. Stern, M. Freedman, and S. Das Sarma, Rev. Mod. Phys. 80, 1083 (2008).

[2] M. C. Dartiailh, W. Mayer, J. Yuan, K. S. Wickramasinghe, A. Matos-Abiague, I. Žutić, and J. Shabani, Phys. Rev. Lett. 126, 036802 (2021).

[3] B. Pekerten, J. D. Pakizer, B. Hawn, and A. Matos-Abiague, Phys. Rev. B 105, 054504 (2022).

[4] J. D. Pakizer, B. Scharf, and A. Matos-Abiague, Phys. Rev. Research 3, 013198 (2021).

[5] J. D. Pakizer and A. Matos-Abiague, Phys. Rev. B 104, L100506 (2021)

[6] T. Zhou, M. C. Dartiailh, K. Sardashti, J. E. Han, A. Matos-Abiague, J. Shabani, and I. Žutić, Nat. Commun. 13, 1738 (2022); T. Zhou, M. C. Dartiailh, W. Mayer, J. E Han, A. Matos-Abiague, J. Shabani, and I. Zutic, Phys. Rev. Lett. 124, 137001 (2020).