New collective mode in YBa2Cu3O6+x observed by time-domain reflectometry

Article

关键词: CHARGE-DENSITY WAVES;    CUPRATE SUPERCONDUCTOR;    COHERENT PHONONS;    HETERODYNE-DETECTION;    RAMAN-SCATTERING;    SPECTROSCOPY;    EXCITATIONS;    YBA2CU3O7-DELTA;    FLUCTUATIONS;    PARTICLES;   

DOI  :  10.1103/PhysRevB.88.060508

来源: SCIE

【 摘 要 】

We report the observation of coherent oscillations associated with charge-density-wave (CDW) order in the underdoped cuprate superconductor YBa2Cu3O6+x by time-resolved optical reflectivity. Oscillations with frequency 1.87 THz onset at approximately 105 and 130 K for dopings of x = 0.67 (ortho-VIII) and x = 0.75 (ortho-III), respectively. Upon cooling below the superconducting critical temperature (T-c), the oscillation amplitude is enhanced, the phase shifts by pi, and the frequency softens by delta nu/nu approximate to 7%. A biquadratically coupled Landau-Ginzburg model qualitatively describes this behavior as arising from competition between superconducting and CDW orders.

【 授权许可】

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