Programme

P.43 -- Poster, VCTP-47

Date: Thursday, 4 August 2022

Time: 08:30 - 10:00

Magnon spectrum of the spin-1 J1 –J2 antiferromagnetic Heisenbeberg model on a triangular lattice

Nguyen Van Hinh (1), Pham Thi Thanh Nga (2), and Nguyen Toan Thang (3)

(1) Hanoi University of Industry, 298 Cau Dien, Bac Tu Liem, Hanoi, Vietnam, (2) Thuyloi University, 175 Tay Son, Dong Da, Hanoi, Vietnam, (3) Institute of Physics, VAST, 10 Dao Tan, Ba Dinh, Hanoi, Vietnam

We study the spin-1 antiferromagnetic Heisenberg model on a triangular lattice with nearest J1 and next-nearest-neighbor J2 exchange interactions. The auxiliary fermionic representation of the spin operators within a functional integral formalism with an imaginary Lagrange multiplier is employed to retain an exact constraint of single particle occupancy. Reprensentating the classical ground state by Luttinger-Tisza procedure one may consider the fluctuation contributions to the free energy of the system in the entire range of the coupling parameters. We derived the magnon spectrum in one-loop approximation. The obtained magnon spectrum is compared with the result of the Green functions Mori’s projection operator technique.

Presenter: Nguyễn Văn Hinh