# Can entangled qubits be disentangled without using code or software?

Is there a way to revert two entangled qubits to a separate state without using code...like restarting a quantum computer?

Note: By "restarting a quantum computer", I do not mean restarting a virtual machine/simulator; I mean restarting a physical quantum computer with physical qubits.

• Pick a physical realization, then can be more specific in answer. – AHusain Jun 4 '19 at 23:41
• Not sure what you mean: You can just measure the qubit and re-initialize it with some physical process, though this will "collapse" the system that the measured qubit was entangled with. If you want to preserve the state of the entangled qubit, but "reset" the original qubit to $|0\rangle$, I don't think this is possible in all cases (such a map might make 2 orthogonal entangled states become non-orthogonal). – Sam Jaques Jun 5 '19 at 2:37
• I mean be more specific like ion or superconducting etc. That way when answering can say what exactly need to do. That way the answer can be something like apply this magnetic field etc. – AHusain Jun 5 '19 at 3:08