The Spin-Boson Model of Condensed Phase (System-Bath) Quantum Dynamics
Statement of Hamiltonian
Physical Origins of the Model:
Multidimensional Tunneling
Electron Phonon Coupling in:
impurity/crystalline systems
intramolecular electron transfer in a polar fluid
Initial conditions of state preparation and the Object of our (Computational) Desire: Time Evolution of the Reduced Density Matrix
Approximate Quantum Dynamics of the Spin-Boson Model for small "hopping matrix element":
Short-time Dynamics: the Fermi Golden Rule
(Heuristic) Method for Extending Short-time Dynamics to Long Times: Kinetic Master Equations (Gain-Loss equations)
Evaluation of Golden Rule rate constants for the Spin-Boson Model (a Problem in Linearly Displaced Harmonic Oscillator Quantum dynamics).
A Better Derivation of Kinetic Master Equations for the Spin-Boson Model (including Memory Effects): the NIBA (Non-Interacting Blip Approximation) for small hopping maxtrix elements.
Some details of NIBA:
the case of strong electron-phonon coupling: the Gaussian approximation and Marcus Theory.
the case of the symmetric Spin Boson model and Ohmic Spectral Density: a survey of results (beyond the Golden Rule).