A review of thermal rectification observations and models in solid materials

Abstract

Thermal rectification is a phenomenon in which thermal transport along a specific axis is dependent upon the sign of the temperature gradient or heat current. This phenomenon offers improved thermal management of electronics as size scales continue to decrease and new technologies emerge by having directions of preferred thermal transport. For most applications where thermally rectifying materials could be of use they would need to exhibit one direction with high thermal conductivity to allow for efficient transport of heat from heat generating components to a sink and one direction with low conductivity to insulate the temperature and heat flux sensitive components. In the process of understanding and developing these materials multiple mechanisms have been found which produce thermally rectifying behavior and much work has been and is being done to improve our understanding of the mechanisms and how these mechanisms can be used with our improved ability to fabricate at the nanoscale to produce efficient materials which have high levels of thermal rectification.

Nonlinear Heat Radiation Induces Thermal Rectifier in Asymmetric Holey Composites

“…Since there are already thermal diodes achieved with different temperature-dependent conductivity (Dames, 2009) or emissivity (Roberts and Walker, 2011), in our study we consider the bulk material itself to be homogenous and isotropic. In the homogenous material, the local heat flux density is expressed as  J T = − ∇ κ , according to Fourier's Law, where J is the heat flux, κ is the material's thermal conductivity and on the vacuum interface of the holes, heat transfer follows the Stefan-Boltzmann Law…”

“…Theoretical models for thermal rectifiers are proposed relying on various mechanisms (Roberts and Walker, 2011), including different temperature-dependent thermal properties between dissimilar materials at a contact (Stevenson et al, 1991;Dames, 2009;Kobayashi et al, 2009), asymmetric design of nanostructure (Wu and Li, 2008;Yang et al, 2009), and quantum thermal systems, such as quantum dots and other quantum heterojunctions (Scheibner et al, 2007;Ruokola et al, 2009;Wu and Segal, 2009;Ren and Zhu, 2013a). Similar concepts are even extended to the spin Seebeck diode and transistor (Ren, 2013;Ren and Zhu, 2013b;Ren et al, 2013), and the multiferroic thermal diode (Chotorlishvili et al, 2015), multiferroic switch and memory .…”

“…It has been well established that asymmetric design and nonlinearity are essential to give rise to thermal rectification (Roberts and Walker, 2011;Li et al, 2012). Thus, there have been more theoretical studies of thermal rectification focusing on nonlinear systems (Wehmeyer et al, 2017).…”

Two-level system in spin baths: Non-adiabatic dynamics and heat transport

“…This Born-Markov limit fundamentally deviates from NIBA predictions comprising a ∆ 2 ω c prefactor, see Eq. (41). This discrepancy may be associated to a recent result showing that in the spin-spin-bath model the dissipative dynamics predicted by the Redfield equation does not conform with NIBA [34].…”

Coherent Caloritronics in Josephson-Based Nanocircuits

“…One, consisting of a NIS junction, and a second one, consisting of a SIS' Josephson tunnel junction [40]. Although never considered in the literature so far for such a purpose [41], superconducting tunnel junctions appear particularly well suited for the implementation of electron heat rectifiers. Heat transport in such structures is deeply influenced by the strong temperature dependence of the superconducting density of states.…”