A quantum computer (or QC for short) can be obtained through the destruction of an AI Edgerunner (aka. ATLAS). They can be brought back to Enceladus Prime for a reward of 250,000 E$.
Obtaining
A QC can be obtained from causing an Edge runner ship to undergo meltdown, where it will be left in place of what would be a lifepod on most ships. It can be collected with a manipulator arm, or collected in a large enough excavator. If your excavator isn't big enough to swallow it, it can still keep a hold on the quantum computer, but do be careful for sharp maneuvers.
If collected properly, it sells for 250,000 E$ at EP