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arXiv · 1709.08790

Light-Enhanced Spin Fluctuations and d-Wave Superconductivity at a Phase Boundary

Yao Wang·Cheng-Chien Chen·B. Moritz·T. P. Devereaux
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Abstract

Time-domain techniques have shown the potential of photo-manipulating existing orders and inducing new states of matter in strongly correlated materials. Using time-resolved exact diagonalization, we perform numerical studies of pump dynamics in a Mott-Peierls system with competing charge and spin density waves. A light-enhanced $d$-wave superconductivity is observed when the system resides near a quantum phase boundary. By examining the evolution of spin, charge and superconducting susceptibilities, we show that a sub-dominant state in equilibrium can be stabilized by photomanipulating charge order to allow superconductivity to appear and dominate. This work provides an interpretation of light-induced superconductivity from the perspective of order competition, and offers a promising approach for designing novel emergent states out of equilibrium.

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Yao Wang, Cheng-Chien Chen, B. Moritz, T. P. Devereaux. 2017-09-26. Light-Enhanced Spin Fluctuations and d-Wave Superconductivity at a Phase Boundary. https://doi.org/10.1103/physrevlett.120.246402

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