中国物理B ›› 2022, Vol. 31 ›› Issue (11): 110304-110304.doi: 10.1088/1674-1056/ac8739
Topological superconductivity in Janus monolayer transition metal dichalcogenides
Xian-Dong Li(李现东)1, Zuo-Dong Yu(余作东)1,2,†, Wei-Peng Chen(陈伟鹏)3,‡, and Chang-De Gong(龚昌德)1,4,5
- 1 National Laboratory of Solid State Microstructure, Department of Physics, Nanjing University, Nanjing 210093, China;
2 School of Information and Electronic Engineering, Zhejiang Gongshang University, Hangzhou 310018, China;
3 Shenzhen Institute for Quantum Science and Engineering, Southern University of Science and Technology, Shenzhen 518055, China;
4 Center for Statistical and Theoretical Condensed Matter Physics, Zhejiang Normal University, Jinhua 321004, China;
5 Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing 210093, China
Topological superconductivity in Janus monolayer transition metal dichalcogenides
Xian-Dong Li(李现东)1, Zuo-Dong Yu(余作东)1,2,†, Wei-Peng Chen(陈伟鹏)3,‡, and Chang-De Gong(龚昌德)1,4,5
- 1 National Laboratory of Solid State Microstructure, Department of Physics, Nanjing University, Nanjing 210093, China;
2 School of Information and Electronic Engineering, Zhejiang Gongshang University, Hangzhou 310018, China;
3 Shenzhen Institute for Quantum Science and Engineering, Southern University of Science and Technology, Shenzhen 518055, China;
4 Center for Statistical and Theoretical Condensed Matter Physics, Zhejiang Normal University, Jinhua 321004, China;
5 Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing 210093, China
摘要： The Janus monolayer transition metal dichalcogenides (TMDs) $MXY$ ($M={\rm Mo}$, W, $etc$. and $X, Y={\rm S}$, Se, $etc$.) have been successfully synthesized in recent years. The Rashba spin splitting in these compounds arises due to the breaking of out-of-plane mirror symmetry. Here we study the pairing symmetry of superconducting Janus monolayer TMDs within the weak-coupling framework near critical temperature $T_{\rm c}$, of which the Fermi surface (FS) sheets centered around both $ărGamma$ and $K (K')$ points. We find that the strong Rashba splitting produces two kinds of topological superconducting states which differ from that in its parent compounds. More specifically, at relatively high chemical potentials, we obtain a time-reversal invariant $s + f + p$-wave mixed superconducting state, which is fully gapped and topologically nontrivial, $i.e.$, a $\mathbb{Z}_2$ topological state. On the other hand, a time-reversal symmetry breaking $d + p + f$-wave superconducting state appears at lower chemical potentials. This state possess a large Chern number $|C|=6$ at appropriate pairing strength, demonstrating its nontrivial band topology. Our results suggest the Janus monolayer TMDs to be a promising candidate for the intrinsic helical and chiral topological superconductors.
中图分类号: (Phases: geometric; dynamic or topological)
- 03.65.Vf