Temperature-independent thermal radiation
Alireza Shahsafi, Patrick Roney, You Zhou, Zhen Zhang, Yuzhe Xiao, Chenghao Wan, Raymond Wambold, Jad Salman, Zhaoning Yu, Jiarui Li, View ORCID ProfileJerzy T. Sadowski, Riccardo Comin, Shriram Ramanathan, and Mikhail A. Kats
PNAS December 26, 2019 116 (52) 26402-26406; first published December 17, 2019 https://doi.org/10.1073/pnas.1911244116
Alireza Shahsafi
aDepartment of Electrical and Computer Engineering, University of Wisconsin–Madison, Madison, WI 53706;
Patrick Roney
bSchool of Engineering and Applied Sciences, Harvard University, Cambridge, MA 02138;
cSchool of Materials Engineering, Purdue University, West Lafayette, IN 47907;
Yuzhe Xiao
Chenghao Wan
aDepartment of Electrical and Computer Engineering, University of Wisconsin–Madison, Madison, WI 53706;dMaterials Science and Engineering, University of Wisconsin–Madison, Madison, WI 53706;
Raymond Wambold
Jad Salman
Zhaoning Yu
aDepartment of Electrical and Computer Engineering, University of Wisconsin–Madison, Madison, WI 53706;eDepartment of Physics, University of Wisconsin–Madison, Madison, WI 53706;
Jiarui Li
fDepartment of Physics, Massachusetts Institute of Technology, Cambridge, MA 02142;
Jerzy T. Sadowski
gCenter for Functional Nanomaterials, Brookhaven National Laboratory, Upton, NY 11973
ORCID record for Jerzy T. Sadowski
Riccardo Comin
Shriram Ramanathan
Mikhail A. Kats
aDepartment of Electrical and Computer Engineering, University of Wisconsin–Madison, Madison, WI 53706;dMaterials Science and Engineering, University of Wisconsin–Madison, Madison, WI 53706;eDepartment of Physics, University of Wisconsin–Madison, Madison, WI 53706;
For correspondence: mkats@wisc.edu
Edited by Evelyn L. Hu, Harvard University, Cambridge, MA, and approved November 12, 2019 (received for review June 30, 2019)
Conventional wisdom states that the hotter an object is, the brighter it glows. This is the case for thermal light at any wavelength and enables applications such as infrared imaging and noncontact thermometry. We demonstrate a coating that emits the same amount of thermal radiation irrespective of temperature, within a temperature range of about 30 °C. This is accomplished using samarium nickel oxide—a quantum material that changes strongly but gradually as a function of temperature. This is the first time that temperature-independent thermal radiation has been demonstrated, and has substantial implications for infrared camouflage, privacy shielding, and radiative heat transfer.
Thermal emission is the process by which all objects at nonzero temperatures emit light and is well described by the Planck, Kirchhoff, and Stefan–Boltzmann laws. For most solids, the thermally emitted power increases monotonically with temperature in a one-to-one relationship that enables applications such as infrared imaging and noncontact thermometry. Here, we demonstrated ultrathin thermal emitters that violate this one-to-one relationship via the use of samarium nickel oxide (SmNiO3), a strongly correlated quantum material that undergoes a fully reversible, temperature-driven solid-state phase transition. The smooth and hysteresis-free nature of this unique insulator-to-metal phase transition enabled us to engineer the temperature dependence of emissivity to precisely cancel out the intrinsic blackbody profile described by the Stefan–Boltzmann law, for both heating and cooling. Our design results in temperature-independent thermally emitted power within the long-wave atmospheric transparency window (wavelengths of 8 to 14 µm), across a broad temperature range of ∼30 °C, centered around ∼120 °C. The ability to decouple temperature and thermal emission opens a gateway for controlling the visibility of objects to infrared cameras and, more broadly, opportunities for quantum materials in controlling heat transfer.
thermal emission
quantum materials
↵1A.S. and P.R. contributed equally to this work.
↵2To whom correspondence may be addressed. Email: mkats{at}wisc.edu.
Author contributions: M.A.K. designed research; A.S., P.R., Y.Z., Z.Z., Y.X., C.W., R.W., J.S., Z.Y., J.L., J.T.S., and M.A.K. performed research; A.S., P.R., Y.Z., Z.Z., Y.X., C.W., J.L., J.T.S., R.C., S.R., and M.A.K. analyzed data; A.S., P.R., S.R., and M.A.K. wrote the paper; and S.R. and M.A.K. supervised the research.
You are going to email the following Temperature-independent thermal radiation
Alireza Shahsafi, Patrick Roney, You Zhou, Zhen Zhang, Yuzhe Xiao, Chenghao Wan, Raymond Wambold, Jad Salman, Zhaoning Yu, Jiarui Li, Jerzy T. Sadowski, Riccardo Comin, Shriram Ramanathan, Mikhail A. Kats
Proceedings of the National Academy of Sciences Dec 2019, 116 (52) 26402-26406; DOI: 10.1073/pnas.1911244116