Execution of qubit gates
One aspect of this disclosure relates to a method for operating a quantum computing device. A request to execute a first n-qubit gate on a set of n target qubits is received. The first n-qubit gate is representable as an m-qubit diagonal gate conjugated by a Clifford gate, where m≤n. A set of m interface qubits on which to perform the m-qubit diagonal gate are identified. A Clifford operation is executed on each interface qubit and its corresponding target qubits. The m-qubit diagonal gate is executed on the set of m interface qubits.
1 . A method, comprising:
receiving a request to execute a first qubit gate on a set of target qubits, the first qubit gate representable as a diagonal gate conjugated by a Clifford gate, where the diagonal gate is executable on a set of interface qubits, the set of interface qubits having at most the same number of qubits as the set of target qubits;
executing Clifford operations on the set of interface qubits and the set of target qubits; and
executing the diagonal gate on the set of interface qubits.
2 . The method of claim 1 , wherein the Clifford operations executed on the set of interface qubits and the set of target qubits are multi-qubit Pauli measurements, and wherein a number of qubits in the first qubit gate is less than or equal to 8 qubits.
3 . The method of claim 2 , wherein the multi-qubit Pauli measurements are executed by using pre-established entanglement.
4 . The method of claim 1 , wherein the Clifford operations executed on the set of interface qubits and the set of target qubits are multi-qubit Pauli gates X-controlled on the set of interface qubits.
5 . The method of claim 4 , wherein the multi-qubit Pauli gates X-controlled on the set of interface qubits are executed using pre-established entanglement.
6 . A method, comprising:
receiving a request to execute a first qubit gate on a first set of target qubits, the first qubit gate representable as a diagonal gate conjugated by a Clifford gate, where the diagonal gate is executable on a set of interface qubits, the set of interface qubits having at most the same number of qubits as the first set of target qubits;
executing Clifford operations on the set of interface qubits and the first set of target qubits;
executing the diagonal gate on the set of interface qubits; and
performing computations on one or more qubits of the first set of target qubits prior to completion of the execution of the diagonal gate on the set of interface qubits.
7 . The method of claim 6 , wherein the Clifford operations executed on the set of interface qubits and the first set of target qubits are multi-qubit Pauli measurements.
8 . The method of claim 7 , wherein the multi-qubit Pauli measurements are executed by using pre-established entanglement.
9 . The method of claim 6 , wherein the Clifford operations executed on the set of interface qubits and the first set of target qubits are multi-qubit Pauli gates X-controlled on the set of interface qubits.
10 . The method of claim 9 , wherein the multi-qubit Pauli gates X-controlled on the set of interface qubits are executed using pre-established entanglement.
11 . The method of claim 6 , further comprising:
receiving a request to execute a second qubit gate on a second set of target qubits, the second set of target qubits including one or more of the first set of target qubits; and
initiating execution of the second qubit gate on the second set of target qubits prior to completion of the execution of the diagonal gate on the set of interface qubits.
12 . The method of claim 11 , wherein executing the second qubit gate on the second set of target qubits includes executing a Clifford operation on one or more qubits of the set of interface qubits and one or more corresponding target qubits of the second set of target qubits.
13 . The method of claim 12 , wherein the Clifford operations executed on one or more qubits of the set of interface qubits and the one or more corresponding target qubits of the second set of target qubits are multi-qubit Pauli measurements.
14 . The method of claim 13 , wherein the multi-qubit Pauli measurements are executed by using pre-established entanglement.
15 . The method of claim 11 , wherein the Clifford operations executed on one or more qubits of the set of interface qubits and the one or more corresponding target qubits of the second set of target qubits are multi-qubit Pauli gates X-controlled on the one or more qubits of the set of interface qubits.
16 . The method of claim 15 , wherein the multi-qubit Pauli gates X-controlled on the one or more qubits of the set of interface qubits are executed using pre-established entanglement.
17 . The method of claim 11 , wherein the method further comprises:
responsive to completing the execution of the diagonal gate on the set of interface qubits, measuring spin along X on the set of interface qubits; and
storing measured spin values for X.
18 . The method of claim 17 , further comprising:
performing multi-qubit Pauli corrections on one or more qubits of the first set of target qubits and the second set of target qubits.
19 . The method of claim 18 , wherein the multi-qubit Pauli corrections are performed by using pre-established entanglement.
20 . A method, comprising:
receiving a request to execute a first qubit gate on a first set of target qubits, and where the first qubit gate is representable as a diagonal gate conjugated by a Clifford gate, where the diagonal gate is executable on a set of interface qubits, the set of interface qubits having at most the same number of qubits as the first set of target qubits;
executing Clifford operations on the set of interface qubits and the first set of target qubits;
executing the diagonal gate on the set of interface qubits;
performing computations on one or more qubits of the first set of target qubits prior to completion of the execution of the diagonal gate on the set of interface qubits;
receiving a request to execute a second qubit gate on a second set of target qubits, the second set of target qubits including one or more qubits of the first set of target qubits;
initiating execution of the second qubit gate on the second set of target qubits prior to completion of the execution of the diagonal gate on the set of interface qubits;
responsive to completing the execution of the diagonal gate on the set of interface qubits, measuring spin along X on the set of interface qubits;
storing measured spin values for X; and
performing multi-qubit Pauli corrections on one or more qubits of the first set of target qubits and the second set of target qubits.