Narrow Results

Using Monte Carlo simulation and mean field approximation, we studied the magnetic properties of spin-3/2 chain with hexagonal spin-1/2 shell and negative core-shell exchange coupling. The obtained results show that the spins 3/2 in the core have an important influence on the magnetic behavior of the system such as the appearance of compensation temperatures as well as first- and second-order phase transitions. Moreover, we investigated the effects of exchange interactions and anisotropy on the phase diagrams of the system.

In this paper, we propose and analyze an efficient high-dimensional quantum state transfer (QST) scheme through an XXZ-Heisenberg spin chain in an inhomogeneous magnetic field. By the use of a combination of coherent quantum coupling and free spin wave approximation, pure unitary evolution results in a perfect high-dimensional swap operation between two remote quantum registers mediated by a uniform quantum data bus and the feasibility is confirmed by numerical simulations. Also, we observe that either the strong z-directional coupling or high quantum spin number can partly suppress the thermal excitations and protect quantum information from the thermal noises when the quantum data bus is in the thermal equilibrium state.

In this paper, we numerically study the non-Abelian statistics of the zero-energy Majorana fermions at the end of Majorana chain and show its application to quantum computing by mapping it to a spin model with special symmetry. In particular, by using transverse-field Ising model with Z2 symmetry, we verify the nontrivial non-Abelian statistics of Majorana fermions. Numerical evidence and comparison in both Majorana representation and spin representation are presented. The degenerate ground states of a symmetry protected spin chain therefore provide a promising platform for topological quantum computation.

A long-range interacting spin chain can exhibit temperature jump at the transition energy under the microcanonical description. After two identical long-range interacting subsystems of the same size at the same temperatures are weakly coupled, they exchange energy and the total microcanonical entropy of the full system increases irreversibly, leading to a violation of the Zeroth Law of Thermodynamics. In addition, microcanonical Monte Carlo simulations are performed to verify our conclusion.