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arXiv · 2009.08598

Direct and ultrafast probing of quantum many-body interaction and Mott-insulator transition through coherent two-dimensional spectroscopy

Nguyen Thanh Phuc·Pham Quang Trung
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Abstract

Interactions between particles in quantum many-body systems play a crucial role in determining the electric, magnetic, optical, and thermal properties of the system. The recent progress in the laser-pulse technique has enabled the manipulations and measurements of physical properties on ultrafast timescales. Here, we propose a method for the direct and ultrafast probing of quantum many-body interaction through coherent two-dimensional (2D) spectroscopy. Up to a moderate interaction strength, the inter-particle interaction manifests itself in the emergence of off-diagonal peaks in the 2D spectrum before all the peaks coalesce into a single diagonal peak as the system approaches the Mott-insulating phase in the strongly interacting regime. The evolution of the 2D spectrum as a function of the time delay between the second and third laser pulses can provide important information on the ultrafast time variation of the interaction.

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Nguyen Thanh Phuc, Pham Quang Trung. 2020-09-18. Direct and ultrafast probing of quantum many-body interaction and Mott-insulator transition through coherent two-dimensional spectroscopy. https://doi.org/10.1103/physrevb.104.115105

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