Abstract

We analyze the stability of Neel and collinear orders for the frustrated {ital J}{sub 1}-{ital J}{sub 2} model on a square lattice as a function of {ital S} and {ital J}{sub 2}/{ital J}{sub 1} within the Schwinger-boson mean-field theory. For Neel order and {ital finite} {ital S}, the domain of stability extends beyond the classical boundary {ital J}{sub 2}/{ital J}{sub 1}=1/2, suggesting the possibility of stabilizing (with the help of quantum fluctuations) a state that is classically forbidden. We use the solution with short-range Neel order as an effective model for the magnetic properties of high-{ital T}{sub {ital c}} Cu oxides. Predictions are made for the static susceptibility, the dynamical structure factor, and the nuclear relaxation rates (all observable experimentally) at all temperatures. We show that the spin waves are overdamped even at low {ital T} and that a gap opens in the spin-fluctuation spectrum. The susceptibility is nearly linear on a wide intermediate temperature range and obeys a Curie law at high temperature in agreement with 1/{ital N} fermionic expansion.

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

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.