Title: Dynamic optical control of near-field radiative transfer

Abstract

Dynamic control of radiative heat transfer is of fundamental interest as well as for applications in thermal management and energy conversion. However, realizing high contrast control of heat flow without moving parts and with high temporal frequencies remains a challenge. Here, we propose a thermal modulation scheme based on optical pumping of semiconductors in near-field radiative contact. External photo-excitation of the semiconductor emitters leads to increases in the free carrier concentration that in turn alters the plasma frequency, resulting in modulation of near-field thermal radiation. Furthermore the temporal frequency of the modulation can reach hundreds of kHz limited only by the recombination lifetime, greatly exceeding the bandwidth of methods based on temperature modulcation. Calculations based on fluctuational electrodynamics show that the heat transfer coefficient between two silicon films can be tuned from near zero to 600 Wm^-2K^-1 with a gap distance of 100 nm at room temperature.

Authors:

Kou, Junlong ;

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• Search DOE PAGES for ORCID "0000-0002-0481-5149"

Minnich, Austin J.

Publication Date:

Tue Jul 24 00:00:00 EDT 2018

Research Org.:

Energy Frontier Research Centers (EFRC) (United States). Light-Material Interactions in Energy Conversion (LMI); California Institute of Technology (CalTech), Pasadena, CA (United States)

Sponsoring Org.:

USDOE Office of Science (SC), Basic Energy Sciences (BES)

OSTI Identifier:

1461583

Alternate Identifier(s):

OSTI ID: 1503306

Grant/Contract Number:  

SC0001293

Resource Type:

Published Article

Journal Name:

Optics Express

Additional Journal Information:

Journal Name: Optics Express Journal Volume: 26 Journal Issue: 18; Journal ID: ISSN 1094-4087

Publisher:

Optical Society of America

Country of Publication:

United States

Language:

English

Subject:

36 MATERIALS SCIENCE; Radiation; Thermal effects; Surface plasmon