Re-investigating the pseudogap phase of cuprates.

The nature of the pseudogap state and the role it plays in the rich phase diagram of cuprate superconductors is yet to be fully understood. It is still an open question whether the transition to this state is a true phase transition or a slow crossover. A further question is whether the phase transition terminates at a zero temperature quantum critical point and what influence this has on the superconductivity. Recently, measurements of in-plane magnetic torque have suggested an abrupt transition close to the estimated edge of the pseudogap phase; suggesting a thermodynamic transition to an electronically nematic state. Here were further investigate these effects in different high Tc cuprates and how extrinsic effects can influence the signals seen.