The phase diagram of the underdoped cuprates at high magnetic field

Understand

The experimentally measured phase diagram of cuprate superconductors in the temperature-applied magnetic field plane illuminates key issues in understanding the physics of these materials.

• At low temperature, the superconducting state gives way to a long-range charge order with increasing magnetic field; both the orders coexist in a small intermediate region.
• The charge order transition is strikingly insensitive to temperature, and quickly reaches a transition temperature close to the zero-field superconducting $T_c$.
• We argue that such a transition along with the presence of the coexisting phase cannot be described simply by a competing orders formalism.