Pressure Effects Show that the Pseudogap Phase of Cuprates is Confined by Fermi Surface Topology
ORAL
Abstract
The pseudogap phase is the central puzzle of cuprate high-temperature superconductors, and why it onsets below a critical doping p* that is much lower in La2−xSrxCuO4 than in La1.6−xNdySrxCuO4 or Bi2Sr2CuO6+δ, for instance, is unknown. We recently performed high-magnetic-field transport measurements in the cuprate La1.6−xNdySrxCuO4 and observed a large and unexpected shift of the pseudogap critical point p* as a function of applied pressure. We find that the shift in p* is driven by a corresponding shift in pFS, the doping at which the large Fermi surface goes from hole-like to electron-like, so that p* ≤ pFS must be obeyed. Consequently, the pseudogap cannot open on an electron-like Fermi surface. This necessary condition for pseudogap formation, imposed by details of the Fermi surface, is a strong constraint for theories of the pseudogap phase. Our finding that p* can be tuned with a modest pressure opens a new route for experimental studies of the pseudogap.
*Work performed in part at the NHMFL. Work funded by NSERC, FRQNT, CFI, and a Canada Research Chair.
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Presenters
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Nicolas Doiron-Leyraud
- Université de Sherbrooke