1210.3088 (A. F. Kemper et al.)

Mapping of the unoccupied states and relevant bosonic modes via the time
dependent momentum distribution    [PDF]

A. F. Kemper, M. Sentef, B. Moritz, C. C. Kao, Z. X. Shen, J. K. Freericks, T. P. Devereaux

The unoccupied states of complex materials are difficult to measure, yet play a key role in determining their emergent properties. We propose a novel technique that can measure the unoccupied states, time-resolved Compton scattering, which measures the time-dependent momentum distribution (TDMD). Using a non-equilibrium Keldysh formalism, we study the TDMD for electrons coupled to a lattice in a pump-probe setup. We find a direct relation between temporal oscillations in the TDMD and the underlying unoccupied states, suggesting that both can be measured by time-resolved Compton scattering.

View original: http://arxiv.org/abs/1210.3088