It's not super conductivity but instead quantum mechanics.
High capacity hard drives nowadays use heat and strong magnetic fields to write patterns into the platter. It's pretty stable just sitting around doing nothing.
High density multi level NAND involves quantum tunneling a few electrons using a strong electric field into an electrically insulated bit of semiconductor. Over some time the electrons tunnel their way out, but usually this only ends up actually happening if too much writing damaged the insulation.
High capacity hard drives nowadays use heat and strong magnetic fields to write patterns into the platter. It's pretty stable just sitting around doing nothing.
High density multi level NAND involves quantum tunneling a few electrons using a strong electric field into an electrically insulated bit of semiconductor. Over some time the electrons tunnel their way out, but usually this only ends up actually happening if too much writing damaged the insulation.