TY - JOUR
T1 - Quantum phase transitions in the hubbard model on a triangular lattice
AU - Yoshioka, Takuya
AU - Koga, Akihisa
AU - Kawakami, Norio
PY - 2009/8/6
Y1 - 2009/8/6
N2 - We investigate the quantum phase transitions in the half-filled Hubbard model on the triangular lattice by means of the path-integral renormalization group method with a new iteration and truncation scheme proposed recently. It is found for a cluster of 36 sites that as the Hubbard interaction U increases, the paramagnetic metallic state undergoes a first-order phase transition to a nonmagnetic insulating (NMI) state at Uc1∼7.4t, which is followed by another first-order transition to a 120°Néel ordered state at Uc2∼9.2t, where t is the transfer integral. The size dependence of the results is also addressed. Our results suggest the existence of the intermediate NMI phase and resolve some controversial arguments on the nature of the previously proposed quantum phase transitions.
AB - We investigate the quantum phase transitions in the half-filled Hubbard model on the triangular lattice by means of the path-integral renormalization group method with a new iteration and truncation scheme proposed recently. It is found for a cluster of 36 sites that as the Hubbard interaction U increases, the paramagnetic metallic state undergoes a first-order phase transition to a nonmagnetic insulating (NMI) state at Uc1∼7.4t, which is followed by another first-order transition to a 120°Néel ordered state at Uc2∼9.2t, where t is the transfer integral. The size dependence of the results is also addressed. Our results suggest the existence of the intermediate NMI phase and resolve some controversial arguments on the nature of the previously proposed quantum phase transitions.
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U2 - 10.1103/PhysRevLett.103.036401
DO - 10.1103/PhysRevLett.103.036401
M3 - Article
AN - SCOPUS:68649126066
VL - 103
JO - Physical Review Letters
JF - Physical Review Letters
SN - 0031-9007
IS - 3
M1 - 036401
ER -