Single Photon Emission from a Plasmonic Light Source Driven by a Local Field-Induced Coulomb Blockade

Area of Science:

• Quantum physics and nanoscale science
• Condensed matter physics
• Materials science

Background:

• Quantum control is essential for manipulating quantum phenomena at the nanoscale.
• Scanning tunneling microscopy-induced luminescence (STML) enables light generation from nanoscale systems.
• Controlling single photon emission is a key challenge in quantum technologies.

Purpose of the Study:

• To demonstrate nanoscale manipulation of quantum emission using STML.
• To investigate the origin and characteristics of single photon emission from C60 films on Ag(111).
• To explore the role of electronic structure and tunneling mechanisms in photon generation.

Main Methods:

• Utilized scanning tunneling microscopy-induced luminescence (STML) to generate light.
• Performed Hanbury Brown and Twiss photon intensity interferometry to confirm single photon emission.
• Conducted tight-binding calculations to model the electronic structure of the tip-Ag-C60 system.

Main Results:

• Generated plasmonic light via inelastic tunneling between a tip and C60 film on Ag(111).
• Observed single photon emission with a recovery time of 0.1 nanoseconds or less, distinct from molecular excitons.
• Calculations showed good agreement with experimental results, identifying electric-field-induced split-off states below the C60 LUMO band as the mechanism.

Conclusions:

• The study demonstrates a method for nanoscale quantum control of light emission.
• Coulomb blockade effects involving split-off states are responsible for single photon emission.
• This technique using split-off states is applicable to narrowband, large-bandgap materials for quantum applications.