Angstrom-scale plasmonic gap boosts nonlinear light output by 2,000% per volt

Researchers at the Institute for Molecular Science (NINS, Japan) and SOKENDAI have demonstrated a more than 2000% voltage-induced enhancement of near-field nonlinear optical responses. To achieve this giant modulation, they focused on an angstrom-scale gap formed between a metallic tip and substrate in a scanning tunneling microscope (STM), which can strongly confine and enhance light intensity through plasmon excitation. The paper is published in the journal Nature Communications.