Question

What is a “charged order parameter”?

Answer 1

Well, it is just a condensate made with charges. The order parameter is the density of 2-electrons correlations (often called Cooper pairs). Since it's charged, it has characteristic properties, like the magnetic vortex quantisation at high magnetic field (and the associated pseudo-levitation), the perfect diamagnetism at low magnetic field, the Little-Parks effect, the Josephson effect and the associated SQUIDs and qubits, the London momentum effect (also called rotating superconductor effect), and so on