Loschmidt echo of a central spin coupled to an XY spin chain: Role of three-site interaction

Effects of two types of three-site interaction, i.e., XZX+YZY and XZY−YZX, on Loschmidt Echo (LE) of a central spin coupled to an XY spin chain are studied. The dynamical evolution behaviors of the LE are investigated analytically and numerically. The XZX+YZY type of three-site interaction (α1) can shift the critical points of the magnetic field λ. At the critical points |λ−α1|=1, the decay of the LE is enhanced. The role of the XZY−YZX type of three-site interaction (α2) depends on its strength. In some specific intervals, α2 can remarkably delay the decay of the LE.