Probing the lattice anharmonicity of superconducting YBa2Cu3O7−δ via phonon harmonics

We examine coherent phonons in a strongly driven sample of optimally-doped high temperature superconductor YBa2Cu3O7−δ . We observe a nonlinear lattice response of the 4.5 THz copper-oxygen vibrational mode at high excitation densities, evidenced by the observation of the phonon third harmonic and i...

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Detalles Bibliográficos
Autores: Ramos Alvarez, Alberto, Fleischmann, Nina, Vidas, Luciana, Fernández Rodríguez, Alejandro, Palau, Anna, Wall, Simon
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2019
País:España
Institución:Consejo Superior de Investigaciones Científicas (CSIC)
Repositorio:DIGITAL.CSIC. Repositorio Institucional del CSIC
OAI Identifier:oai:digital.csic.es:10261/199865
Acceso en línea:http://hdl.handle.net/10261/199865
Access Level:acceso abierto
Palabra clave:Electron-phonon coupling
Optical phonons
Superconducting fluctuations
Superconducting phase transition
Ultrafast phenomena
Cuprates
High-temperature superconductors
Unconventional superconductors
Descripción
Sumario:We examine coherent phonons in a strongly driven sample of optimally-doped high temperature superconductor YBa2Cu3O7−δ . We observe a nonlinear lattice response of the 4.5 THz copper-oxygen vibrational mode at high excitation densities, evidenced by the observation of the phonon third harmonic and indicating the mode is strongly anharmonic. In addition, we observe how high-amplitude phonon vibrations modify the position of the electronic charge transfer resonance. Both of these results have important implications for possible phonon-driven nonequilibrium superconductivity