Bright, circularly polarized black-body radiation from twisted nanocarbon filaments
Jun Lu, Hong Ju Jung, Ji‐Young Kim, Nicholas A. Kotov
Abstract
Planck's law ignores but does not prohibit black-body radiation (BBR) from being circularly polarized. BBR from nanostructured filaments with twisted geometry from nanocarbon or metal has strong ellipticity from 500 to 3000 nanometers. The submicrometer-scale chirality of these filaments satisfies the dimensionality requirements imposed by fluctuation-dissipation theorem and requires symmetry breaking in absorptivity and emissivity according to Kirchhoff's law. The resulting BBR shows emission anisotropy and brightness exceeding those of conventional chiral photon emitters by factors of 10 to 100. The helical structure of these filaments enables precise spectral tuning of the chiral emission, which can be modeled using electromagnetic principles and chirality metrics. Encapsulating nanocarbon filaments in refractive ceramics produces highly efficient, adjustable, and durable chiral emitters capable of functioning at extreme temperatures previously considered unattainable.