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Pump Built-in Hamiltonian Method for Pump-Probe Spectroscopy

Jun-ichi Inoue·Akira Shimizu
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Abstract

We propose a new method of calculating nonlinear optical responses of interacting electronic systems. In this method, the total Hamiltonian (system + system-pump interaction) is transformed into a different form that (apparently) does not have a system-pump interaction. The transformed Hamiltonian, which we call the pump built-in Hamiltonian, has parameters that depend on the strength of the pump beam. Using the pump built-in Hamiltonian, we can calculate nonlinear responses (responses to probe beams as a function of the pump beam) by applying the {\em linear} response theory. We demonstrate the basic idea of this new method by applying it to a one-dimensional, two-band model, in the case the pump excitation is virtual (coherent excitation). We find that the exponent of the Fermi edge singularity varies with the pump intensity.

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Jun-ichi Inoue, Akira Shimizu. 1999-05-08. Pump Built-in Hamiltonian Method for Pump-Probe Spectroscopy. https://doi.org/10.1143/jpsj.68.2534

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