Repository logo
 

Superconductivity. Quasiparticle mass enhancement approaching optimal doping in a high-T(c) superconductor.


Type

Article

Change log

Authors

Ramshaw, BJ 
Sebastian, SE 
McDonald, RD 
Day, James 
Tan, BS 

Abstract

In the quest for superconductors with higher transition temperatures (T(c)), one emerging motif is that electronic interactions favorable for superconductivity can be enhanced by fluctuations of a broken-symmetry phase. Recent experiments have suggested the existence of the requisite broken-symmetry phase in the high-T(c) cuprates, but the impact of such a phase on the ground-state electronic interactions has remained unclear. We used magnetic fields exceeding 90 tesla to access the underlying metallic state of the cuprate YBa2Cu3O(6+δ) over a wide range of doping, and observed magnetic quantum oscillations that reveal a strong enhancement of the quasiparticle effective mass toward optimal doping. This mass enhancement results from increasing electronic interactions approaching optimal doping, and suggests a quantum critical point at a hole doping of p(crit) ≈ 0.18.

Description

Keywords

0202 Atomic, Molecular, Nuclear, Particle and Plasma Physics

Journal Title

Science

Conference Name

Journal ISSN

0036-8075
1095-9203

Volume Title

348

Publisher

American Association for the Advancement of Science (AAAS)
Sponsorship
European Research Council (337425)
This work is supported by the US Department of Energy BES \Science at 100 T," the National Science Foundation, the State of Florida, the Natural Science and Engineering Research Council of Canada and the Canadian Institute for Advanced Research. S.E.S. ac- knowledges support from the Royal Society and the European Research Council under the European Union's Seventh Framework Programme (FP7/2007-2013) / ERC Grant Agree- ment no. 337425.