Related Experiment Video
Updated: May 17, 2026

Resonance Fluorescence of an InGaAs Quantum Dot in a Planar Cavity Using Orthogonal Excitation and Detection
Published on: October 13, 2017
Bias, Length, or Coupling: What Controls the Quantum Efficiency of Molecular Electroluminescence?
Facundo Tarasi1, Esteban D Gadea2, Tchavdar N Todorov3
1Departamento de Química Inorgánica, Analítica y Química Física/INQUIMAE, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, C1428EHA Buenos Aires, Argentina.
Abstract:
Using currents to control light emission of individual molecules has multiple motivations, including organic light-emitting diode design and the development of display technologies, optical interconnects in nanoscale circuits, chemical reaction mapping and detection with molecular resolution, optoelectronic logic gates, or single-photon sources for quantum control. However, experiments struggle to discern the specific roles of intrinsic and extrinsic factors on the emitted power and the quantum efficiency. Among such factors, the applied potential, the electrode coupling, and the molecular length are critical. Through carefully validated time-dependent quantum electrodynamics modeling, we decipher how these parameters can be chosen to achieve an exponential enhancement in the electroluminescence efficiency of individual polymers, with polyphenylenevinylene and two other aromatic oligomers as case studies. In particular, we show that the applied bias is the primary factor determining emission power, while the quantum efficiency is mostly controlled by the polymer length.
More Related Videos
Related Concept Videos
Variables Affecting Phosphorescence and Fluorescence
Photoluminescence: Fluorescence and Phosphorescence
A pair of electrons in a...
Molecular Spectroscopy: Absorption and Emission
Photoluminescence: Applications
Biasing of P-N Junction
In equilibrium, no external voltage is applied across the p-n junction. The depletion region is formed at the junction interface due to the diffusion of carriers, which leaves behind charged dopants, acceptors on the p-side, and donors on the n-side. These immobile charges create an electric field that prevents further diffusion of carriers. The related energy band...
Gene Regulation in Microbial Communities: Quorum Sensing

