Regular Article

Effect of lattice period on thermal current of Frenkel-Kontorova lattices

¹ College of Civil Engineering and Architecture, Kunming University of Science and Technology, Kunming 650500, P.R. China
² Yunnan Reascend Tobacco Technology (Group) Co., Ltd, Kunming 650000, P.R. China

^a e-mail: zhangjqxy@163.com

Received: 29 August 2018
Received in final form: 1 November 2018
Published online: 13 December 2018

Abstract

Effect of lattice period on thermal current of Frenkel-Kontorova (FK) lattices in the underdamped case is investigated by means of numerical calculations. The results indicate that: (i) the negative differential thermal resistance (NDTR) effect completely depends on the period of the FK lattice in the case of fixed amplitude of on-site potential. With the increment of the lattice period, the NDTR effect is gradually disappearing. (ii) For the specific lattice period (a = 0.15), the system’s symmetry greatly affects the NDTR phenomenon. The NDTR effect becomes more and more obvious with the increment of V_R. (iii) If the lattice periods of the two segments of coupled FK nonlinear lattices are not equal, the NDTR phenomenon can also occur even though the on-site potential is in symmetry (V_L = V_R = 1). Meanwhile, with the increment of the average environmental reference temperature, the NDTR gradually disappears. Our results indicate that the lattice period of nonlinear lattices plays a crucial role in the design of thermal devices.