Optically induced coherent transport far above Tc in underdoped YBa2Cu3O6+δ

  title={Optically induced coherent transport far above Tc in underdoped YBa2Cu3O6+$\delta$},
  author={Stefan Kaiser and Cassandra R. Hunt and Daniele Nicoletti and W. J. Hu and Isabella Gierz and H. Y. Liu and Mathieu le Tacon and Toshinao Loew and D. Haug and Bernhard Keimer and Andrea Cavalleri},
  journal={Physical Review B},
We report on a photo-induced transient state of YBa2Cu2O6+x in which transport perpendicular to the Cu-O planes becomes highly coherent. This effect is achieved by excitation with mid-infrared optical pulses, tuned to the resonant frequency of apical oxygen vibrations, which modulate both lattice and electronic properties. Below the superconducting transition temperature Tc, the equilibrium signatures of superconducting interlayer coupling are enhanced. Most strikingly, the optical excitation… 

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