High pressure, high magnetic fields fermiology studies of YBCO.

The pnictide, cuprate and molecular conductor families exhibit similar phase diagrams, leading to a great deal of interest in a common mechanism for a “universal phase diagram”. The typical ingredients for such phase diagrams include an antiferromagnetic phase, a superconducting dome, and possibly one, or several quantum critical points (QCP). Chemical doping is one traditional way to look at such materials, however thermodynamic variables such as magnetic field or hydrostatic pressure have proven to be powerful tools to explore this phase diagram, with very strong magnetic fields being used to suppress the superconducting dome, allowing one to investigate the QCP.

We report on our high pressure (up to 25GPa) and high fields (up to 85T) Quantum Oscillation measurements of the Fermi surface of YBCO6.5.