Coherent perfect absorption in deeply subwavelength films in the single-photon regime

• Main Authors: Roger, Thomas, Vezzoli, Stefano, Bolduc, Eliot, Valente, Joao, Heitz, Julius J. F., Jeffers, John, Soci, Cesare, Leach, Jonathan, Couteau, Christophe, Zheludev, Nikolay I., Faccio, Daniele
• Other Authors: School of Physical and Mathematical Sciences
• Format: Article
• Language: English
• Published: 2018
• Subjects: Single Photons and Quantum Effects; DRNTU::Science::Physics::Optics and light; Nanoparticles
• Online Access: https://hdl.handle.net/10356/89108; http://hdl.handle.net/10220/46134
• Institution: Nanyang Technological University

The technologies of heating, photovoltaics, water photocatalysis and artificial photosynthesis depend on the absorption of light and novel approaches such as coherent absorption from a standing wave promise total dissipation of energy. Extending the control of absorption down to very low light levels and eventually to the single-photon regime is of great interest and yet remains largely unexplored. Here we demonstrate the coherent absorption of single photons in a deeply subwavelength 50% absorber. We show that while the absorption of photons from a travelling wave is probabilistic, standing wave absorption can be observed deterministically, with nearly unitary probability of coupling a photon into a mode of the material, for example, a localized plasmon when this is a metamaterial excited at the plasmon resonance. These results bring a better understanding of the coherent absorption process, which is of central importance for light harvesting, detection, sensing and photonic data processing applications.