Method and system for observing a subject at a first location based upon quantum properties measured at a second location

• US 7,847,234 B2
• Filed: 12/23/2008
• Issued: 12/07/2010
• Est. Priority Date: 08/06/2003
• Status: Expired due to Fees

• Current Assignee: United States Of America As Represented By The Secretary Of The Army (Government of the United States of America)
• Original Assignee: The United States Of America As Represented By The Secretary Of The Army
• Inventors: Meyers, Ronald Everett, Deacon, Keith Scott
• Primary Examiner(s): Le; Que T
• Application Number:
  US12/343,384
• Publication Number:
  US 20090194702A1
• Time in Patent Office: 714 Days
• Field of Search: 250/221, 250/222.1, 250/225, 250/214.R, 250/214.1, 250/559.4, 356/301, 356/317, 356/318, 356/322, 356/327, 356/453, 356/487, 356/491, 356/367, 356/368, 380/44, 380/283, 380/256, 380/278
• US Class Current: 250/225
• CPC Class Codes: H04L 9/0858 Details about key distillation or coding, e.g. reconciliation, error correction, privacy amplification, polarisation coding or phase coding

Abstract

A preferred embodiment comprises a method and system for (a) detecting objects or targets which may or may not be nonreflective to electromagnetic radiation, and/or (b) generating an image of a subject or area, comprising generating an entangled photon pair beam; splitting the entangled photon pair beam into first and second parts; the first parts being directed in a first direction towards a first location, and the second parts being received into a measuring device; measuring the physical characteristics of the conjugate second parts to determine whether or not the first parts have encountered the presence or absence of an object at the first location in combination with the time that the first part takes to enter the first location. The method and system incorporate a photon beam in a reference path that never directly interacts with the object yet is determinative of presence or absence of an object at the first location. The splitting of the entangled photon pair beam occurs prior to the first parts being absorbed by said object, and the measuring of the characteristics of the conjugates occurs subsequent to the splitting of the entangled photon beam.

Claims

1. A system for detecting information concerning a subject comprising;

a processor for processing information;

at least one entangled photon light source;

a splitter for splitting the entangled photons into first and second parts, the first parts being directed to a subject at a first location and the second parts being directed to a receiver at a second location;

the receiver at the second location being operatively connected to the processor;

the receiver at the second location operative to receive the second parts and detect spatial information relating to the influence of the subject on the first parts based upon the second parts;

a timer for measuring the time of travel for the second parts from the light source to the receiver at the second location;

the processor operating to correlate the time of travel of the second parts with the spatial information derived from the receiver at a correlating interval of time to detect the subject at the first location.

2. The system of claim 1 wherein the presence or absence of a subject is determined using the measurement of the second parts at synchronized time intervals by using the equation:

G⁽²⁾({right arrow over (ρ

)}_o,{right arrow over (ρ

)}_i)=G₁₁⁽¹⁾({right arrow over (ρ

)}₁,{right arrow over (ρ

)}₁)G₂₂⁽¹⁾({right arrow over (ρ

)}₂,{right arrow over (ρ

)}₂)+G₁₂⁽¹⁾({right arrow over (ρ

)}₁,{right arrow over (ρ

)}₂)G₂₁⁽¹⁾({right arrow over (ρ

)}₂,{right arrow over (ρ

)}₁)

where G₁₁⁽¹⁾ G₂₂⁽¹⁾ is approximately equal to G₀ and G₀ is a constant, and G₁₂⁽¹⁾ G₂₁⁽¹⁾ is approximately equal to δ

(ρ

₁±

ρ

₂) where δ

(ρ

₁±

ρ

₂) represents the δ

-function non-local position-position correlation; and

ρ

₁ and ρ

₂ are the transverse spatial vector coordinates of the object and the detector used for measuring the second parts, respectively, and where the effect of the object at ρ

₁ is derived from the ratios and/or differences and/or products and sums of the photon properties measured at ρ

₂ in lieu of recorded measurements in the terms G₁₁⁽¹⁾ and G₁₂⁽¹⁾ G₂₂⁽¹⁾ at location ρ

₁.

3. The system of claim 1 wherein the splitter comprises a beam splitter and wherein the properties of the entangled photons generated by the at least one entangled photon light source includes two different colors which are superimposed in each of said first and second parts such that the influence of an object in the subject location on the first parts will result in the conjugate color being detected by the receiver.

4. The system of claim 1 wherein the properties of the entangled photons generated by the at least one entangled photon light source includes two different polarizations which are superimposed in each of said first and second parts such that the influence of an object in the subject location on the first parts will result in the conjugate polarization being detected by the receiver.

5. The system of claim 1 wherein the properties of the entangled photons generated by the at least one entangled photon light source includes two different spins which are superimposed in each of said first and second parts such that the influence of an object in the subject location on the first parts will result in the conjugate spin being detected by the receiver.

6. The system of claim 1 wherein the properties of the entangled photons generated by the at least one entangled photon light source includes two different angular momenta which are superimposed in each of said first and second parts such that the influence of an object in the subject location on the first parts will result in the conjugate angular momentum being detected by the receiver.

7. The system of claim 1 wherein the splitter is a 50/50 beam splitter which splits the second parts into a nonpolarizing beam splitter, which directs certain of the second parts into a charged coupled device and the remainder into a dichroic beam splitter which splits the second parts into two color bucket detectors.

8. The system of claim 1 wherein the second location is remote from the subject and wherein the second portions are used to generate an image of the subject.

9. The system of claim 1 wherein the properties of the entangled photon parts are affected by the subject;

and wherein the influence of the subject on the first parts will result in the conjugate quantum characteristic being detected by the receiver.

10. The system of claim 1 wherein the entangled photon parts which are received into the receiver never directly interact with the subject yet are determinative of whether or not the properties of the entangled quantum particles are affected by the subject.

11. The system of claim 1 wherein the first parts travel though an obscuring medium such as fog, an aerosol, gas, particulate, turbulence, liquid, or frosted glass en route to the first location and wherein the subject is observed through the obscuring medium based upon quantum characteristics recorded by the receiver.