Quantum communication link robust against photon loss

Patent metadata

Field	Value
Publication number	US-10594408-B2
Application number	US-201816225300-A
Country	US
Kind code	B2
Filing date	Dec 19, 2018
Priority date	Mar 7, 2017
Publication date	Mar 17, 2020
Grant date	Mar 17, 2020

Abstract

A technique relates to communication of a quantum state. Polarization hardware is configured to receive a polarization encoded qubit and split the polarization encoded qubit into two qubits. A converter is coupled to the polarization hardware, and the converter is configured to convert the two qubits into a form suitable for a CNOT gate. The CNOT gate is configured to receive the two qubits such that a measurement result of a CNOT operation of the CNOT gate determines success of the communication of the quantum state.

First claim

What is claimed is:

1. A system for communication, the system comprising:
a CNOT gate configured to receive two qubits, the CNOT gate being configured to entangle the two qubits;
a converter coupled to the CNOT gate, the converter being configured to convert the two qubits into a form suitable for a polarization hardware; and
the polarization hardware configured to receive the two qubits and combine the two qubits into a polarization encoded qubit for a communication.

2. The system of claim 1 , wherein the CNOT gate includes a target qubit and a control qubit.

3. The system of claim 2 , wherein a first qubit of the two qubits is the control qubit and a second qubit of the two qubits is the target qubit.

4. The system of claim 3 , wherein the polarization hardware includes a polarizing beam combiner configured to combine the two qubits, thereby forming the polarization encoded qubit.

5. The system of claim 3 , wherein the polarization encoded qubit is configured to cause a zero (0) on another target qubit as an indication of success of the communication of a quantum state on another control qubit.

6. The system of claim 5 , wherein the polarization encoded qubit is configured to cause a one (1) on the another target qubit as indication of failure of the communication of the quantum state on the another control qubit.

7. The system of claim 6 , wherein the polarization encoded qubit is configured to cause the 0 on the another target qubit as confirmation of receipt of a destination qubit on the another control qubit, the destination qubit being in a form of a|0 +b|1 .

8. The system of claim 7 , wherein the polarization encoded qubit is configured to cause the 1 on the target qubit as confirmation of no receipt of the destination qubit on the control qubit.

9. The system of claim 1 , wherein the converter is configured to convert the two qubits into the polarization encoded qubit.

10. A system for communication, the system comprising:
a CNOT gate configured to receive two qubits, the CNOT gate bring configured to entangle the two qubits;
a converter coupled to be CNOT gate, the converter being configured to convert the two qubits into a form suitable for a polarization hardware; and
the polarization hardware configured to receive the two qubits and combine the two qubits into a polarization encoded qubit for a communication;
wherein the polarization hardware includes a polarization shifter.

11. A communication method comprising:
receiving two qubits;
entangling, using a CNOT gate, the two qubits;
converting, using a converter coupled to the CNOT gate, the two qubits into a form suitable for a polarization hardware; and
combining, using the polarization hardware, the two qubits into a polarization encoded qubit for a communication;
wherein the polarization hardware includes a polarization shifter.

12. The method of claim 11 , wherein the CNOT gate includes a target qubit and a control qubit.

13. The method of claim 12 , wherein a first qubit of the two qubits is the control qubit and a second qubit of the two qubits is the target qubit.

14. The method of claim 13 , wherein the polarization hardware includes a polarizing beam combiner configured to combine the two qubits, thereby forming the polarization encoded qubit.

15. The method of claim 14 , wherein the polarization shifter is configured to shift either the first qubit or the second qubit.

16. The method of claim 13 , wherein the polarization encoded qubit is configured to cause a zero (0) on another target qubit as an indication of success of the communication of a quantum state on another control qubit.

17. The method of claim 16 , wherein the polarization encoded qubit is configured to cause a one (1) on the another target qubit as indication of failure of the communication of the quantum state on the another control qubit.

18. The method of claim 17 , wherein the polarization encoded qubit is configured to cause the 0 on the another target qubit as confirmation of receipt of a destination qubit on the another control qubit, the destination qubit being in a form of a|0 +b|1 .

19. The method of claim 18 , wherein the polarization encoded qubit is configured to cause the 1 on the target qubit as confirmation of no receipt of the destination qubit on the control qubit.

20. The method of claim 11 , wherein the converter is configured to convert the two qubits into the polarization encoded qubit.

Assignees

• IBM

Inventors

• Bishop Lev S
• Gambetta Jay M
• Paik Hanhee

Classifications

• H04B10/70 Primary

  Photonic quantum communication · CPC title

• G06N10/00

  Quantum computing, i.e. information processing based on quantum-mechanical phenomena · CPC title