Lateral and flexural thermal transport in stanene/2D-SiC van der Waals heterostructure
Shihab Ahammed, Md. Sherajul Islam, Imon Mia, Jeongwon Park
Abstract
Abstract Thermal management is one of the key challenges in nanoelectronic and optoelectronic devices. The development of a van der Waals heterostructure (vdWH) using the vertical positioning of different two-dimensional (2D) materials has recently appeared as a promising way of attaining desirable electrical, optical, and thermal properties. Here, we explore the lateral and flexural thermal conductivity of stanene/2D-SiC vdWH utilizing the reverse non-equilibrium molecular dynamics simulation and transient pump-probe technique. The effects of length, area, coupling strength and temperature on the thermal transport are studied systematically. The projected lateral thermal conductivity of a stanene/2D-SiC hetero-bilayer is found to be 66.67 <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:mrow> <mml:mtext> </mml:mtext> </mml:mrow> <mml:mi>W</mml:mi> <mml:mrow> <mml:mtext> </mml:mtext> </mml:mrow> <mml:mrow> <mml:msup> <mml:mi>m</mml:mi> <mml:mrow> <mml:mo>−</mml:mo> <mml:mn>1</mml:mn> </mml:mrow> </mml:msup> </mml:mrow> <mml:mrow> <mml:msup> <mml:mi>K</mml:mi> <mml:mrow> <mml:mo>−</mml:mo> <mml:mn>1</mml:mn> </mml:mrow> </mml:msup> </mml:mrow> </mml:math> , which is greater than stanene, silicene, germanene, MoSe 2 and even higher than some hetero-bilayers, including MoS 2 /MoSe 2 and stanene/silicene. The lateral thermal conductivity increases as the length increases, while it tends to decrease with increasing temperature. The computed flexural interfacial thermal resistance between stanene and 2D-SiC is 3.0622 <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:mo>×</mml:mo> </mml:math> <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:mrow> <mml:msup> <mml:mn>10</mml:mn> <mml:mrow> <mml:mo>−</mml:mo> <mml:mn>7</mml:mn> </mml:mrow> </mml:msup> </mml:mrow> </mml:math> K.m 2 W −1 , which is close to other 2D hetero-bilayers. The interfacial resistance between stanene and 2D-SiC is reduced by 70.49% and 50.118% as the temperature increases from 100 K to 600 K and the coupling factor increases from <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:mrow> <mml:mrow> <mml:mi>χ</mml:mi> </mml:mrow> </mml:mrow> <mml:mo>=</mml:mo> <mml:mn>0.5</mml:mn> </mml:math> to <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:mrow> <mml:mrow> <mml:mi>χ</mml:mi> </mml:mrow> </mml:mrow> <mml:mo>=</mml:mo> <mml:mn>5</mml:mn> </mml:math> , respectively. In addition, various phonon modes are evaluated to disclose the fundamental mechanisms of thermal transport in the lateral and flexural direction of the hetero-bilayer. These results are important in order to understand the heat transport phenomena of stanene/2D-SiC vdWH, which could be useful for enhancing their promising applications.