title: Tailoring high-temperature radiation and the resurrection of the incandescent source.
abstract: In solar cells, the mismatch between the Sun's emission spectrum and the cells' absorption profile limits the efficiency of such devices, while in incandescent light bulbs, most of the energy is lost as heat. One way to avoid the waste of a large fraction of the radiation emitted from hot objects is to tailor the thermal emission spectrum according to the desired application. This strategy has been successfully applied to photonic-crystal emitters at moderate temperatures, but is exceedingly difficult for hot emitters (>1,000 K). Here, we show that a plain incandescent tungsten filament (3,000 K) surrounded by a cold-side nanophotonic interference system optimized to reflect infrared light and transmit visible light for a wide range of angles could become a light source that reaches luminous efficiencies (∼40%) surpassing existing lighting technologies, and nearing a limit for lighting applications. We experimentally demonstrate a proof-of-principle incandescent emitter with efficiency approaching that of commercial fluorescent or light-emitting diode bulbs, but with exceptional reproduction of colours and scalable power. The ability to tailor the emission spectrum of high-temperature sources may find applications in thermophotovoltaic energy conversion and lighting.
authors.affiliation: Research Laboratory of Electronics, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA.
authors.forename: Ognjen
authors.initials: O
authors.lastname: Ilic
authors.affiliation: School of Electrical and Computer Engineering, Birck Nanotechnology Center, Purdue University, West Lafayette, Indiana 47906, USA.
authors.forename: Peter
authors.identifier: http://orcid.org/0000-0001-7140-0667
authors.initials: P
authors.lastname: Bermel
authors.affiliation: Department of Mechanical Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA.
authors.forename: Gang
authors.identifier: http://orcid.org/0000-0002-3968-8530
authors.initials: G
authors.lastname: Chen
authors.affiliation: Research Laboratory of Electronics, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA.
authors.forename: John D
authors.initials: JD
authors.lastname: Joannopoulos
authors.affiliation: Research Laboratory of Electronics, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA.
authors.forename: Ivan
authors.initials: I
authors.lastname: Celanovic
authors.affiliation: Research Laboratory of Electronics, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA.
authors.forename: Marin
authors.initials: M
authors.lastname: Soljačić