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Spectral and Angle-Resolved Magneto-Optical Characterization of Photonic Nanostructures
Published on: November 21, 2019
Multidimensional optical spectroscopy of a single molecule in a current-carrying state
1Department of Chemistry, University of California, Irvine, California 92697, USA.
The Journal of Chemical Physics
|January 5, 2011
Summary
We calculated nonlinear optical signals from molecules connected to metallic leads using a superoperator formalism. Coherent stimulated emission and incoherent fluorescence provide similar, but distinct, information about molecular charge states.
Area of Science:
- Quantum optics
- Molecular electronics
- Condensed matter theory
Background:
- Understanding nonlinear optical signals is crucial for characterizing molecular systems.
- Open quantum systems coupled to metallic leads present complex dynamics.
Purpose of the Study:
- To calculate nonlinear optical signals from a molecule-lead system under pulsed excitation.
- To compare information obtained from coherent stimulated emission and incoherent fluorescence detection schemes.
Main Methods:
- Utilized a superoperator formalism to model the open quantum system.
- Evaluated superoperator correlation functions via Hilbert space operators and Wick's theorem for superoperators.
- Calculated nonequilibrium two-point Green's functions.
Main Results:
- Developed a method to compute nonlinear optical signals from molecule-lead systems.
- Demonstrated that coherent and incoherent detection yield similar yet distinct information.
- Observed resonances involving multiple molecular charge states in stimulated Raman scattering.
Conclusions:
- The superoperator formalism provides a robust framework for studying nonlinear optics in molecular junctions.
- Coherent and incoherent spectroscopies offer complementary insights into open quantum systems.
- Resonant processes can probe charge state dynamics within molecules.
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