A density matrix approach for the electroluminescence of molecules in a scanning tunneling microscope

Abstract

The electroluminescence of molecules confined inside a nanocavity in the scanning tunneling microscopy possesses many intriguing but unexplained features. We present here a general theoretical approach based on the density matrix formalism to describe the electroluminescence from molecules near a metal surface induced by both electron tunneling and local surface plasmon excitations simultaneously. It reveals the underlying physical mechanism for the external bias dependent electroluminescence. The important role played by the local surface plasmon on the electroluminescence is highlighted. Calculations for porphyrin derivatives have reproduced corresponding experimental spectra and nicely explained the observed unusual large variation of emission spectral profiles. This general theoretical approach can find many applications in the design of molecular electronic and photonic devices.

4 pages, 3 figures

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Cited by in corpus (6)

• Electronic Structure and Superconductivity of FeSe-Related Superconductors
• Narrow-line single-molecule transducer between electronic circuits and surface plasmons
• Tunneling-current-induced local excitonic luminescence in p-doped WSe${}_2$ monolayers
• Effects of Interference between Energy Absorption Processes of Molecule and Surface Plasmons on Light Emission Induced by Scanning Tunneling Microscopy
• Interplay between Plasmon Luminescence and Vibrationally Resolved Molecular Luminescence Induced by Scanning Tunneling Microscopy
• Signatures of Plexcitonic States in Molecular Electroluminescence