Normal State Nernst Effect in Electron-doped Pr2-xCexCuO4: Superconducting Fluctuations and Two-band Transport

Abstract

We report a systematic study of normal state Nernst effect in the electron-doped cuprates Pr${}_{2-x}$Ce${}_x$CuO${}_{4-\delta }$ over a wide range of doping (0.05$\le x\le$0.21) and temperature. At low temperatures, we observed a notable vortex Nernst signal above T${}_c$ in the underdoped films, but no such normal state vortex Nernst signal is found in the overdoped region. The superconducting fluctuations in the underdoped region are most likely incoherent phase fluctuations as found in hole-doped cuprates. At high temperatures, a large normal state Nernst signal is found at dopings from slightly underdoped to highly overdoped. Combined with normal state thermoelectric power, Hall effect and magnetoresistance measurements, the large Nernst effect is compatible with two-band model. For the highly overdoped films, the large Nernst effect is anomalous and not explainable with a simple hole-like Fermi surface seen in photoemission experiments.

9 pages, 8 figures, accepted in PRB

References in corpus (5)

• Theory of the Nernst effect near quantum phase transitions in condensed matter, and in dyonic black holes
• Nernst effect in semi-metals: the meritorious heaviness of electrons
• High-field Hall resistivity and magnetoresistance in electron-doped Pr_2-xCe_xCuO_{4-δ}
• Superfluid response in electron-doped cuprate superconductors
• Staggered flux vortices and the superconducting transition in the layered cuprates

Cited by in corpus (3)

• The Nernst effect and the boundaries of the Fermi liquid picture
• Enhancement of the Nernst effect by stripe order in a high-Tc superconductor
• Giant Nernst Effect due to Fluctuating Cooper Pairs in Superconductors