Abstract |
Topological superconductor (TSC) design and modulation is one of the most important but challenging task for its great potential in the topological quantum computations. In this talk, taking FeSe0.5Te0.5 and PdBi2Te4 as example, I will introduce a new paradigm to design TSC in the ideal superconducting topological metal (SCTM). 1. In 2016, we innovatively propose a new scheme to realize TSC in ideal SCTM, which host the inverted band structures and superconductivity simultaneously. The TSC properties of FeSe0.5Te0.5, as well as Majorana zero modes (MZMs) at its end of vortex line, are calculated for the first time, which are confirmed by experimental observations in 2018. 2. Recently, we propose a new strategy to design the ideal SCTMs by intercalating superconducting units PdTe (or PdTe2) into topological insulator Bi2Te3, and develop a general program to calculate the TSC spectrum and its topological invariant from ab initio calculations. Our results predicts that PdBi2Te4 and PdBi2Te5 are experimentally synthesizable and ideal SCTMs, which host both the topological surface states at the Fermi level and superconductivity at 3.11 K and 0.57 K respectively. Then the chiral TSC phases are confirmed under our program for the slab calculations by incorporating topological surface states with Zeeman effect. Our results pave a new way to realize TSC and MZMs in a large class of materials and provide a general tool to design and modulate the TSC system from ab initio calculations. |
