Super-Planckian electron cooling in a van der Waals stack
Abstract
Radiative heat transfer (RHT) between macroscopic bodies at separations that are much smaller than the thermal wavelength is ruled by evanescent electromagnetic modes and can be orders of magnitude more efficient than its far-field counterpart, which is described by the Stefan-Boltzmann law. In this Letter we present a microscopic theory of RHT in van der Waals stacks comprising graphene and a natural hyperbolic material, i.e. hexagonal boron nitride (hBN). We demonstrate that RHT between hot carriers in graphene and hyperbolic phonon-polaritons in hBN is extremely efficient at room temperature, leading to picosecond time scales for the carrier cooling dynamics.
This work was supported by the European Union's Horizon 2020 research and innovation programme under Grant agreement No. 696656 "GrapheneCore1", Fondazione Istituto Italiano di Tecnologia, the Spanish Ministry of Economy and Competitiveness through the "Severo Ochoa" Programme for Centres of Excellence i.- Publication:
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APS March Meeting Abstracts
- Pub Date:
- 2018
- Bibcode:
- 2018APS..MARF36001P