Abstract
The Hubbard model extended by next-nearest-neighbor (NNN) hopping t′ at quarter filling has been investigated numerically using exact diagonalization technique on a small cluster. We report the role of frustration (NNN hopping) on the ground-state properties of the system. The effects of both positive and negative t′ are considered. Results show that a short range antiferromagnetic order is present in the system, which is favored (suppressed) by negative (positive) t′. It appears that electron-electron correlation decreases with NNN hopping interaction. Inclusion of t′ facilitates electron hopping. Though pairing in the extended s-wave channel is dominant for quarter-filled unfrustrated system, d-wave pairing becomes dominant with the inclusion of negative t′.
Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
