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

Mickaël Buret (1) , Igor Smetanin (2) , Alexander Uskov (2) , Gérard Colas Des Francs (1) , Alexandre Bouhelier (1)

1 ICB - Laboratoire Interdisciplinaire Carnot de Bourgogne
2 LPI RAS - P. N. Lebedev Physical Institute of the Russian Academy of Sciences [Moscow]

We observe anomalous visible to near-infrared electromagnetic emission from electrically driven atomicsize 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.

Mots clés: electromigration; point contact; quantized conductivity; visible light emission; Bremsstrahlung

Domaines: Matière Condensée [cond-mat]

Mickaël Buret, Igor Smetanin, Alexander Uskov, Gérard Colas Des Francs, Alexandre Bouhelier. Effect of quantized conductivity on the anomalous photon emission radiated from atomic-size point contacts. Nanophotonics, 2019, 9, pp.413 - 425. ⟨10.1515/nanoph-2019-0325⟩. ⟨hal-02373080⟩