Effect of quantized conductivity on the anomalous photon emission radiated from atomic-size point contacts

Abstract

We observe anomalous visible to near-infrared electromagnetic emission from electrically driven atomic-size point contacts. We show that the number of photons released strongly depends on the quantized conductance steps of the contact. Counterintuitively, the light intensity features an exponential decay dependence with the injected electrical power. We propose an analytical model for the light emission considering an out-of-equilibrium electron distribution. We treat photon emission as a Bremsstrahlung process resulting from hot electrons colliding with the metal boundary, and find qualitative accord with the experimental data.

Keywords

• electromigration
• point contact
• quantized conductivity
• visible light emission
• bremsstrahlung