Multi-control quantum state inversion gate
In a quantum circuit, an inversion gate is implemented with two controls each connected to a control qubit. In the quantum circuit responsive to determining that each control of the inversion gate is currently connected to a control qubit, an ancilla gate is implemented, a first control of the ancilla gate connected to a control qubit moved from a first control of the inversion gate, a second control of the ancilla gate connected to a control qubit selected from the set of unplaced control qubits, a target of the ancilla gate connected to the first control of the inversion gate. At a gate implemented in the quantum circuit responsive to determining that the gate has a maximum number of controls not connected to control qubits, a control of the gate is connected to a control qubit selected from the set of unplaced control qubits.
1. A method comprising:
implementing, in a quantum circuit, an inversion gate, the inversion gate configured to invert a quantum state of a target input if every control is in a |1 quantum state, the inversion gate having two controls, the controls each connected to a control qubit selected from a set of unplaced control qubits;
implementing, in the quantum circuit responsive to determining that each control of the inversion gate is currently connected to a control qubit, a first ancilla gate, the first ancilla gate comprising an inversion gate, a first control of the first ancilla gate connected to a control qubit moved from a first control of the inversion gate, a second control of the first ancilla gate connected to a control qubit selected from the set of unplaced control qubits, a target of the first ancilla gate connected to the first control of the inversion gate; and
connecting, at a gate implemented in the quantum circuit responsive to determining that the gate has a maximum number of controls not connected to control qubits, a control of the gate to a control qubit selected from the set of unplaced control qubits.
2. The method of claim 1 , further comprising:
implementing, in the quantum circuit, a mirror ancilla gate, the mirror ancilla gate having the same controls and target as the first ancilla gate, the mirror ancilla gate placed following the inversion gate.
3. The method of claim 1 , wherein the inversion gate comprises a regular inversion gate.
4. The method of claim 3 , wherein the regular inversion gate comprises two controls.
5. The method of claim 4 , wherein the regular inversion gate comprises a SWAP and ten CNOTs.
6. The method of claim 1 , wherein the first ancilla gate comprises a regular inversion gate.
7. The method of claim 6 , wherein the regular inversion gate comprises two controls.
8. The method of claim 1 , wherein the first ancilla gate comprises a relative-phase inversion gate.
9. The method of claim 8 , wherein the relative-phase inversion gate comprises two controls.
10. The method of claim 9 , wherein the relative-phase inversion gate comprises three CNOTs and does not include a SWAP.
11. The method of claim 9 , wherein the relative-phase inversion gate comprises three controls.
12. The method of claim 11 , wherein the relative-phase inversion gate comprises six CNOTs and does not include a SWAP.
13. A computer usable program product comprising one or more computer-readable storage medium, and program instructions stored on at least one of the one or more storage medium, the stored program instructions comprising:
program instructions to implement, in a quantum circuit, an inversion gate, the inversion gate configured to invert a quantum state of a target input if every control is in a |1 quantum state, the inversion gate having two controls, the controls each connected to a control qubit selected from a set of unplaced control qubits;
program instructions to implement, in the quantum circuit responsive to determining that each control of the inversion gate is currently connected to a control qubit, a first ancilla gate, the first ancilla gate comprising an inversion gate, a first control of the first ancilla gate connected to a control qubit moved from a first control of the inversion gate, a second control of the first ancilla gate connected to a control qubit selected from the set of unplaced control qubits, a target of the first ancilla gate connected to the first control of the inversion gate; and
program instructions to connect, at a gate implemented in the quantum circuit responsive to determining that the gate has a maximum number of controls not connected to control qubits, a control of the gate to a control qubit selected from the set of unplaced control qubits.
14. The computer usable program product of claim 13 , wherein the inversion gate comprises a regular inversion gate.
15. The computer usable program product of claim 14 , wherein the regular inversion gate comprises two controls.
16. The computer usable program product of claim 15 , wherein the regular inversion gate comprises a SWAP and ten CNOTs resource requirement of the first analysis operation.
17. The computer usable program product of claim 13 , wherein the first ancilla gate comprises a regular inversion gate.
18. The computer usable program product of claim 13 , wherein the computer usable code is stored in a computer readable storage medium in a data processing system, and wherein the computer usable code is transferred over a network from a remote data processing system.
19. The computer usable program product of claim 13 , wherein the computer usable code is stored in a computer readable storage medium in a server data processing system, and wherein the computer usable code is downloaded over a network to a remote data processing system for use in a computer readable storage medium associated with the remote data processing system.
20. A computer system comprising one or more processors, one or more computer-readable memories, and one or more computer-readable storage medium, and program instructions stored on at least one of the one or more storage medium for execution by at least one of the one or more processors via at least one of the one or more memories, the stored program instructions comprising:
program instructions to implement, in a quantum circuit, an inversion gate, the inversion gate configured to invert a quantum state of a target input if every control is in a |1 quantum state, the inversion gate having two controls, the controls each connected to a control qubit selected from a set of unplaced control qubits;
program instructions to implement, in the quantum circuit responsive to determining that each control of the inversion gate is currently connected to a control qubit, a first ancilla gate, the first ancilla gate comprising an inversion gate, a first control of the first ancilla gate connected to a control qubit moved from a first control of the inversion gate, a second control of the first ancilla gate connected to a control qubit selected from the set of unplaced control qubits, a target of the first ancilla gate connected to the first control of the inversion gate; and
program instructions to connect, at a gate implemented in the quantum circuit responsive to determining that the gate has a maximum number of controls not connected to control qubits, a control of the gate to a control qubit selected from the set of unplaced control qubits.