Inexpensive lead iodide can support phonon-polaritons, compressing/ confining light at nanoscale, enabling THz photonic microcircuits

https://www.eurekalert.org/news-releases/1126815

"6G needs THz, but wavelengths too long for compact microchips... overcome: dissolve salt in water creating supersaturated solution, crystallize heating to 80°C, couple light/ phonons within lead iodide lattice confinement compressing THz into <1 μm regions (original wavelength 100s of μm)... lead iodide light-vibration oscillations persist for long time before dissipating, stabilizing data transmission... photonic microcircuits faster/ generate less heat... waveguides, resonators, beam splitters/ modulators"