  MeV-scale magnetic fields in the interiors of magnetars suppress the pairing
of neutrons and protons in the $S$-wave state. In the case of a neutron
condensate the suppression is the consequence of the Pauli-paramagnetism of the
neutron gas, i.e., the alignment of the neutron spins along the magnetic field.
The proton $S$-wave pairing is suppressed because of the Landau diamagnetic
currents of protons induced by the field. The Ginzburg-Landau and BCS theories
of the critical magnetic fields for unpairing are reviewed. The macrophysical
implications of the suppression (unpairing) of the condensates are discussed
for the rotational crust-core coupling in magnetars and the neutrino-dominated
cooling era of their thermal evolution.
