Program

P.49 -- Poster, NCTP-41

Date: Wednesday, 3 August 2016

Time: 08h30 - 10h00

The spatially anisotropic triangular lattice antiferromagnet: Popov-Fedotov method

Pham Thi Thanh Nga (1), Phan Thu Trang (2) and Nguyen Toan Thang (3)

(1) Thuy loi University, 175 Tay Son, Hanoi; (2) Hanoi National University of Education, 136 Xuan Thuy, Hanoi; (3) Institute of Physics, 10 Dao Tan, Hanoi.

We present an analysic of the antiferomagnetic Heisenberg model on an triangular lattice with spatially anisotropic J1-J2 exchange interactions. We apply the Popov-Fedotov method based on introducing an imaginary valued chemical potential to enforce the auxiliary fermion constraint exactly. The staggered magnetization, magnon spectra, the ground state energy are computed in one loop approximation and compared using two different constraints: exact and on average. In the limit of zero temperature the results are identical, whereas at higher temperature significant differences are found: The comparisons with the results obtained by other methods are discussed.

Presenter: Pham Thi Thanh Nga