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Probing anomalous relaxation by coherent multidimensional optical spectroscopy

F. Sanda·S. Mukamel
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Abstract

We propose to study the origin of algebraic decay of two-point correlation functions observed in glasses, proteins, and quantum dots by their nonlinear response to sequences of ultrafast laser pulses. Power-law spectral singularities and temporal relaxation in two-dimensional correlation spectroscopy (2DCS) signals are predicted for a continuous time random walk model of stochastic spectral jumps in a two level system with a power-law distribution of waiting times $ψ(t)\sim t^{-α-1}$. Spectroscopic signatures of stationary ensembles for $1<α<2$ and aging effects in nonstationary ensembles with $0<α<1$ are identified.

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F. Sanda, S. Mukamel. 2007-01-11. Probing anomalous relaxation by coherent multidimensional optical spectroscopy. https://doi.org/10.1103/physrevlett.98.080603

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