Anomalies-Rich Floquet superconductivities induced by joint modulation of dynamic driving and static parameters

• Published in: New journal of physics Vol. 26; no. 3; pp. 33045 - 33060
• Main Authors: Wang, Donghao, Cen, Cong, Lu, Liangliang, Li, Mengyao, Ding, Zixuan, Tao, Yongchun, Hu, Jingguo
• Format: Journal Article
• Language: English
• Published: Bristol IOP Publishing 01.03.2024
• Subjects: Chemical potential; Energy gap; Floquet systems; Majorana fermions; Parameters; Phase modulation; Phase transitions; Phases; Sandwich structures; Topological insulators; topological materials; topological phases of matter; Topological superconductors; Tuning
• ISSN: 1367-2630; 1367-2630
• DOI: 10.1088/1367-2630/ad33cf

Abstract Current theoretical and experimental endeavors to realize an anomalous Floquet chiral topological superconductor (TSC), which is characterized by chiral Majorana edge modes independent of the Chern number, remain insufficient. Herein, we propose a new scheme that involves jointly tuning dynamic driving and static parameters within a magnetic topological insulator-superconductor sandwich structure to achieve this goal. The Josephson phase modulation induced by an applied bias voltage across the structure is utilized as a Floquet periodic drive. It is found that the interplay between the two kinds of tunings can bring about a lot more exotic Floquet TSC phases than those caused by only tuning the dynamic driving parameter (frequency ω or period τ ). More importantly, just tuning static parameters (the chemical potential µ , Zeeman field g z , and proximity-induced superconducting energy gap Δ b ) also can induce a series of novel topological phase transitions. Particularly, the features in the context of the three tunings are different from each other, originating from the combination of intrinsic and different extrinsic mechanisms. In addition, jointly tuning τ and µ ( g z ) can have its own unique TSC phases. The proposed scheme should be readily accessible in experiments, and thus the family of anomalous Floquet TSC phases may be considerably enriched.