Programme

P.51 -- Poster, VCTP-44

Date: Tuesday, 30 July 2019

Time: 08:30 - 10:00

Magnetic orders of Heisenberg models with arbitrary spin in semi-fermionic representation

Pham Thi Thanh Nga (1) and Nguyen Toan Thang (2)

(1) Thuy loi University, 175 Tay Son, Dong Da, Hanoi. (2) Institute of Physics, 10 Dao Tan, Hanoi.

In 1988 Popov and Fedotov (PF) proposed a new method for spin Hamiltonians free of the local constraint problem for spin S = 1/2 and S = 1. Later, this approach has been extended for arbitrary spin. PF formalism has been used to study magnetic orders in some spin S = 1/2 and S = 1 Heisenberg models. In this report we show how to study the low temperature phases of quantum Heisenberg models with arbitrary spin by means of PF method. We work out the free energy and the magnetization in one-loop approximation.

Presenter: Pham Thị Thanh Nga