The matrix product state (MPS) is utilized to investigate the ground state properties and quantum phase transitions (OPTs) of the dimerized antiferromagnetic Heisenberg (DAH) model. The ground state MPS wavefunc...The matrix product state (MPS) is utilized to investigate the ground state properties and quantum phase transitions (OPTs) of the dimerized antiferromagnetic Heisenberg (DAH) model. The ground state MPS wavefunctions determined by the infinite time-evolving block decimation (iTEBD) algorithm are shown to be very efficient descriptions of DAH model. In the thermodynamic limit, the quantum entanglement, the bond energy~ and the nearest-neighbor correlations are calculated. It is revealed that the singular behavior of the bipartite entanglement can detect the QPTs directly. The critical point J2c= 1.0 is determined evidently, and the quantum phase transition is argued to belong to the second-order category. At the critical point, logarithmic divergent character of the block entanglement is observed, and the system can be described by a free bosonic field theory.展开更多
基金Supported by the Chinese National Science Foundation under Grant Nos.11047160 and 10874003It is also partially supported by the National Basic Research Program of China under Grant No.2009CB939901
文摘The matrix product state (MPS) is utilized to investigate the ground state properties and quantum phase transitions (OPTs) of the dimerized antiferromagnetic Heisenberg (DAH) model. The ground state MPS wavefunctions determined by the infinite time-evolving block decimation (iTEBD) algorithm are shown to be very efficient descriptions of DAH model. In the thermodynamic limit, the quantum entanglement, the bond energy~ and the nearest-neighbor correlations are calculated. It is revealed that the singular behavior of the bipartite entanglement can detect the QPTs directly. The critical point J2c= 1.0 is determined evidently, and the quantum phase transition is argued to belong to the second-order category. At the critical point, logarithmic divergent character of the block entanglement is observed, and the system can be described by a free bosonic field theory.