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arXiv · 1905.08362

Ultrafast Quantum-path Interferometry Revealing the Generation Process of Coherent Phonons

Kazutaka G. Nakamura·Kensuke Yokota·Yuki Okuda·Rintaro Kase·Takashi Kitashima·Yu Mishima·Yutaka Shikano·Yosuke Kayanuma
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Abstract

Optical dual-pulse pumping actively creates quantum-mechanical superposition of the electronic and phononic states in a bulk solid. We here made transient reflectivity measurements in an n-GaAs using a pair of relative-phase-locked femtosecond pulses and found characteristic interference fringes. This is a result of quantum-path interference peculiar to the dual-pulse excitation as indicated by theoretical calculation. Our observation reveals that the pathway of coherent phonon generation in the n-GaAs is impulsive stimulated Raman scattering at the displaced potential due to the surface-charge field, even though the photon energy lies in the opaque region.

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Kazutaka G. Nakamura, Kensuke Yokota, Yuki Okuda, Rintaro Kase, Takashi Kitashima, Yu Mishima, Yutaka Shikano, Yosuke Kayanuma. 2019-05-20. Ultrafast Quantum-path Interferometry Revealing the Generation Process of Coherent Phonons. https://doi.org/10.1103/physrevb.99.180301

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