科研之友
微信
新浪微博
Facebook
分享链接
摘要
Magnetic field effect on the structure of the ground state of a two-dimensional quantum Heisenberg magnet is analyzed. A plaquette representation is used to solve the self-consistent problem and calculate the collective excitation spectrum in a magnetic field. Conditions are found for quantum transition between non-magnetic and oblique antiferromagnetic phases. The change in the ground state of the system is associated with disappearance of the gap in the spin excitation spectrum. Effects of frustration and magnetic field on the spectrum are analyzed. A phase diagram of stable singlet and magnetically ordered phases is presented.
- 出版日期2007-7
