Spin-dependent tunnelling time in phosphorene superlattice

Abstract

ABSTRACT We study theoretically the Hartman effect and spin-dependent group delay time in a strained phosphorene superlattice in the presence of Rashba spin–orbit interaction (RSOI). It is found that the total group delay time depends on the spin degree of freedom. Thus, spin filtering can be obtained in the time domain by means of the phosphorene superlattice. The total group delay time can be efficiently controlled by the angles of incidence of electrons, strength of RSOI and number of superlattice barriers. Particularly, the magnitude of the total group delay time can be tuned via the direction and strength of strain. Therefore, in phosphorene superlattice the total group delay time can be efficiently adjusted mechanically. Moreover, in a strained phosphorene superlattice the superluminal tunnelling or Hartman effect can be observed even for a normal incident.