Coherent Perfect Absorption in Metamaterials with Entangled Photons
Quantum nonlocality, i.e., the presence of strong correlations in spatially separated systems that are forbidden by local realism, lies at the heart of quantum communications and quantum computing. Here, we use polarization-entangled photon pairs to demonstrate a nonlocal interaction of light with a plasmonic structure. Through the detection of one photon with a polarization-sensitive device, we can prevent or allow absorption of a second, remotely located photon. We demonstrate this with pairs of entangled photons in polarization, one of which is coupled into a plasmon of a thin metamaterial absorber in the path of a standing wave of an interferometer. Thus, we realize a quantum eraser experiment using photons and plasmonic resonances from metamaterials that promises opportunities for probabilistic quantum gating and controlling plasmon–photon conversion and entanglement. Moreover, by using the so-called coherent perfect absorption effect, we can expect near-perfect interaction.