BOUNDLESS READING OF INFORMATION BITS WITH A SINGLE PHOTON

• US 20130292472A1
• Filed: 05/04/2012
• Published: 11/07/2013
• Est. Priority Date: 05/04/2012
• Status: Active Grant

• Current Assignee: Raytheon BBN Technologies Corp. (Rtx Corporation)
• Original Assignee: Raytheon BBN Technologies Corp. (Rtx Corporation)
• Inventors: Guha, Saikat
• Granted Patent: US 8,849,124 B2
• Time in Patent Office: Days
• US Class Current: 235/454
• CPC Class Codes: H04B 10/70 Photonic quantum communication

Abstract

An optical imaging system includes a transmitter configured to generate spatially entangled quantum states of light to probe reflective targets, a target configured to reflect the spatially entangled quantum states of light and a receiver configured to receive and detect the spatially entangled quantum states of light, thereby decoding a message encoded in a memory.

Claims

1. An optical imaging system, comprising:

a transmitter configured to generate spatially entangled quantum states of light to probe reflective targets;

a target configured to reflect the spatially entangled quantum states of light; and

a receiver configured to receive and detect the spatially entangled quantum states of light, thereby decoding a message encoded in a memory.

2. The system as claimed in claim 1 where the spatially entangled quantum state of light includes exactly one photon, or more than one photon.

3. The system as claimed in claim 1 further comprising a light source coupled to the transmitter.

4. The system as claimed in claim 3 wherein the transmitter includes an array of optical mode transformation devices.

5. The system as claimed in claim 4 wherein the spatially entangled quantum states of light is configured to pass through the array of optical mode transformation devices to place the spatially entangled quantum states of light in a coherent superposition of multiple phase and spatial locations.

6. The system as claimed in claim 4 wherein the optical mode transformation devices generate an M mode W-state.

7. The system as claimed in claim 4 wherein the optical mode transformation devices are 50-50 balanced beam splitters.

8. The system as claimed in claim 4 wherein the optical mode transformation devices are made of, but not limited to the following passive optical devices:

volume holograms, phase plates, spatial light modulators, and beam splitters.

9. The system as claimed in claim 8 wherein a number of beamsplitters in the array of optical mode transformation devices is M−

1.

10. The system as claimed in claim 4 further comprising an array of light detectors coupled to the receiver.

11. The system as claimed in claim 10 wherein the receiver includes an array of M log 2M/2 beamsplitters.

12. The system as claimed in claim 2 wherein the target is an optically-readable reflective encoded medium.

13. The system as claimed in claim 12 wherein the optically-readable reflective encoded medium uses a binary phase modulation and a Hadamard-code.

14. The system as claimed in claim 12 wherein the spatially entangled quantum states of light is phase modulated upon reflection from the optically encoded medium.

15. An optical imaging system, comprising:

a light source configured to generate light;

a W-state transmitter optically coupled to the light source and configured to place the light in a spatially entangled quantum state;

a binary phase Hadamard coded optical memory in optical communication with the W-state transmitter and configured to modulate the light in the quantum entangled state;

a receiver configured to coalesce the modulated light in the quantum entangled state from a coherent superposition of multiple spatial locations to a light state into one mode that can be easily detected; and

an array of light detectors configured to detect the light state.

16. The system as claimed in claim 15 wherein the transmitted quantum entangled state is a W-state and the return quantum entangled state is a phase-modulated spatially-entangled state.

17. The system as claimed in claim 15 wherein the light is a photon in a Fock state, given by |1.

18. The system as claimed in claim 17 wherein the binary phase Hadamard coded optical memory includes M memory cells.

19. The system as claimed in claim 18 wherein the light that interrogates the M memory cells of the binary phase Hadamard coded optical memory is given by:

|−

|W_M≡

(|−

|10 . . . 0+|−

|01 . . . 0+ . . . +|−

|00 . . . 1)/√

M

20. The system as claimed in claim 17 wherein upon reflection of the light from the binary phase Hadamard coded optical memory, the light is given by:

|−

|W_M≡

(|−

|10 . . . 0−

|−

|01 . . . 0−

. . . −

|−

|00 . . . 1)/√

M.

21. An optical reading method, comprising:

generating light;

placing the light in spatially entangled quantum state of light;

reflecting the light from an optically encoded medium;

coalescing the light at an array of light detectors; and

decoding bits of information from the light.

22. The method as claimed in claim 21 wherein the light in the quantum entangled state is in a coherent superposition of multiple phase and spatial locations.

23. The method as claimed in claim 21 wherein the light is a photon in a Fock state given by |1.