Nanoscale solid-state cooling: a review

Abstract

The recent developments in nanoscale solid-state cooling are reviewed. This includes both theoretical and experimental studies of different physical concepts, as well as nanostructured material design and device configurations. We primarily focus on thermoelectric, thermionic and thermo-magnetic coolers. Particular emphasis is given to the concepts based on metal-semiconductor superlattices, graded materials, non-equilibrium thermoelectric devices, Thomson coolers, and photon assisted Peltier coolers as promising methods for efficient solid-state cooling. Thermomagnetic effects such as magneto-Peltier and Nernst-Ettingshausen cooling are briefly described and recent advances and future trends in these areas are reviewed. The ongoing progress in solid-state cooling concepts such as spin-calorimetrics, electrocalorics, non-equilibrium/nonlinear Peltier devices, superconducting junctions and two-dimensional materials are also elucidated and practical achievements are reviewed. We explain the thermoreflectance thermal imaging microscopy and the transient Harman method as two unique techniques developed for characterization of thermoelectric microrefrigerators. The future prospects for solid-state cooling are briefly summarized.

Thermionic junction devices utilizing phonon blocking

“…Control of heat flux at small length scales is crucial for numerous solid-state electronic devices and systems. In addition to the thermal management of information and communication devices (1), the mastering of heat transfer channels down to the nanoscale also enables, e.g., new memory components (2), high-sensitivity detectors and sensors (3)(4)(5), energy harvesters (6), and compact electronic refrigerators (7). These devices typically use electrothermal elements, the operation of which is based on the correlation between heat/energy and charge carrier currents and requires minimization of the thermal conductance to the bath and maximization of the electrothermal response.…”

Active Peltier Coolers Based on Correlated and Magnon-Drag Metals

“…Similarly, heat management is the limiting step in the further miniaturization of integrated circuits, many of which have time-dependent heat loads. [2][3][4] Solid-state compact coolers without moving parts are of high interest in thermal management [5][6][7] . They are particularly suitable to cooling problems where the thermal load is transient.…”

High-Performance Thermionic Cooling Devices Based on Tilted-Barrier Semiconductor Heterostructures

“…We then investigate nanoscaled cooling devices in which transport of electron and phonon become strongly ballistic and whose working principle applies far from equilibrium. This is the field of thermionic cooling which raises the opportunity to obtain higher cooling efficiency than in conventional thermoelectric devices 9 .…”