Quantum Tunneling in an Order-Parameter-Preserving Antiferromagnet

We have studied quantum tunneling in an order-parameter-preserving antiferromagnet with the help of Holstein-Primakoff transformation. It is found that, when the system being prepared in a coherent state, there exist the quantum tunneling between lattices k and k+1, k and k−1, respectively. In particular, when the lattice is infinitely long and the spin excitations are in the long-wavelength limit, quantum tunneling disappear between lattices k and k+1, and that k and k−1, in this case the magnetic soliton appears.