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Dynamical symmetry breaking under core excitation in graphite: Polarization correlation in soft X-ray recombination emission

Y. Harada·T. Tokushima·Y. Takata·T. Takeuchi·Y. Kitajima·S. Tanaka·Y. Kayanuma·S. Shin
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Abstract

A recombination emission spectrum is applied to study the local lattice distortion due to core excitation in graphite. The recombination emission spectrum reveals a long low-energy tail when the C $1s$ electron is excited to the $σ^*$ core exciton state. This indicates a large local lattice distortion around the excited carbon atom within a core hole lifetime ($\sim$10fs). Theoretical calculation based upon an ionic cluster model well reproduces the experiments. The strong polarization correlation between incident and emitted X-rays is conclusive evidence of symmetry breaking in the core exciton state due to coupling with asymmetric vibrational modes.

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Y. Harada, T. Tokushima, Y. Takata, T. Takeuchi, Y. Kitajima, S. Tanaka, Y. Kayanuma, S. Shin. 2003-11-30. Dynamical symmetry breaking under core excitation in graphite: Polarization correlation in soft X-ray recombination emission. https://doi.org/10.1103/physrevlett.93.017401

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