Electrical modulation of emissivity

Simon Vassant (1) , Ioana Cristina Moldovan Doyen (1) , François Marquier (1) , F. Pardo (2) , Ulf Gennser (2) , Antonella Cavanna (2) , Jean-Luc Pelouard (2) , Jean-Jacques Greffet (1)

1 Laboratoire Charles Fabry / Naphel
2 LPN - Laboratoire de photonique et de nanostructures

We demonstrate that it is possible to modulate the thermal emission through an electrical modulation of the emissivity. The basic idea is to design a device where absorption is due to a resonant phenomenon. If the resonance can be electrically controlled, then absorption and, therefore, thermal emission can be controlled. We demonstrate this general concept using THz resonant absorption by surface phonon polaritons coupled through a gold grating. In our device, absorption is mostly due to a surface phonon mode confined in a single quantum well (QW). The THz emissivity is electrically controlled by controlling the quantum well refractive index using a gate voltage to modulate the electron density. This paves the way to electrically modulated incandescent sources

Domains: Optics / Photonic; Optics [physics.optics]

Simon Vassant, Ioana Cristina Moldovan Doyen, François Marquier, F. Pardo, Ulf Gennser, et al.. Electrical modulation of emissivity. Applied Physics Letters, 2013, 102 (8), pp.081125. ⟨10.1063/1.4793650⟩. ⟨hal-00821552⟩