Scott Edward Spence

US Patent:

7006635, Feb 28, 2006

Filed:

Aug 30, 2001

Appl. No.:

09/943433

Inventors:

Allen D. Parks - Fredericksburg VA, US
Gregory A. Balchin - Alexandria VA, US
Scott E. Spence - Fredericksburg VA, US

Assignee:

The United States of America as represented by the Secretary of the Navy - Washington DC

International Classification:

H04L 9/00
H04L 5/00
H04L 7/00
G06F 1/12
G06F 13/42

US Classification:

380263, 713400, 713401

Abstract:

A method for synchronizing a master clock to a slave clock located in master and slave devices communicating with one another via a laser signal beam and a communications channel, each of the devices including a homodyne detector for determining a respective correlation pattern with respect to a phase tuned local oscillator includes steps for recording master and slave correlation patterns while the signal beam cycles between first and second operating modes, transmitting the master correlation pattern and associated first and second times at which the signal beam shifted between the first and second operating modes and between the second and first operating modes over the communications channel, comparing a portion of the master correlation pattern between the first and second times to the slave correlation pattern to thereby determine the time offset between the master and slave correlation patterns, and applying the time offset to the slave clock. A corresponding clock synchronization system is also described.

US Patent:

8149494, Apr 3, 2012

Filed:

Aug 6, 2008

Appl. No.:

12/228322

Inventors:

Scott E. Spence - Fredericksburg VA, US

Assignee:

The United States of America as represented by the Secretary of the Navy - Washington DC

International Classification:

G02F 1/01
G02B 1/10
G02B 27/12

US Classification:

359288, 359583, 359639

Abstract:

A monolithic Mach-Zehnder Interferometer (MZI) is provided for photon beam-splitting and beam-combining with accurate super-positioning of the outgoing beams, which creates the interference. The MZI includes a complimentary pair of right-isosceles triangular prisms, and several reflector units. The triangular prisms are configurable to physically join together along associated hypotenuse surfaces that form a beam-splitter interface, thereby producing a rectangular prism having a square cross-section with four outer side surfaces. Each reflector unit forms a right-isosceles mirror that rigidly faces a corresponding surface of the four outer side surfaces of the rectangular prism. The MZI further includes a spacer disposed between the corresponding surface and the each reflector unit.

US Patent:

8411278, Apr 2, 2013

Filed:

Jul 26, 2011

Appl. No.:

13/136902

Inventors:

Allen D. Parks - Spotsylvania VA, US
Scott E. Spence - Fredericksburg VA, US

Assignee:

The United States of America as Represented by the Secretary of the Navy - Washington DC

International Classification:

G01B 9/02
G01B 11/02
G01P 3/36

US Classification:

356450, 356 285, 356482, 356493, 356498

Abstract:

An accelerometer instrument is provided for measuring acceleration. The instrument includes a laser, a Mach-Zender interferometer (MZI), a mechanical spring, a detector, a camera, and an analyzer. The laser emits a coherent light beam of photons. The MZI includes first and second beam-splitters along with first and second mirrors. The first mirror has an established mass m and connects to the spring for vibrating substantially perpendicular to its reflection plane. The mechanical spring has an established spring constant k. The MZI has an established weak measurement Nbased on a known offset ε for the beam-splitters. The detector detects the beam beyond the second beam-splitter. The camera provides a pointer measurement shift δq of the photons. The camera is disposed after the detector. The analyzer determines the acceleration α based on.

US Patent:

8514478, Aug 20, 2013

Filed:

Nov 14, 2011

Appl. No.:

13/373749

Inventors:

Scott E. Spence - Fredericksburg VA, US

Assignee:

The United States of America as Represented by the Secretary of the Navy - Washington DC

International Classification:

G02F 1/01
G02B 1/10
G02B 27/12

US Classification:

359288, 359583, 359639

Abstract:

A two-photon absorption (TPA) switch is provided for minimizing which-path information in quantum optic interference. The TPA switch includes a pulse laser, first and second dichroic mirrors, a down-conversion crystal, a reflector, and a beam-splitter. The pulse laser emits a pump photon traveling along a photon-incident direction. The dichroic mirrors are disposed along the incident direction and oriented to enable photons to either pass there-through or perpendicularly reflect perpendicular to the incident direction. The down-conversion crystal is disposed between the dichroic mirrors along the incident direction and is non-critically phase-matched with signal and idler photons controlled by temperance of the crystal. The beam-splitter is disposed along one of the reflection directions to probabilistically reflect one of the signal and idler photons to pass through the crystal.

US Patent:

8520214, Aug 27, 2013

Filed:

Jul 13, 2011

Appl. No.:

13/135975

Inventors:

Allen D. Parks - Spotsylvania VA, US
Scott E. Spence - Fredericksburg VA, US

Assignee:

The United States of America as Represented by the Secretary of the Navy - Washington DC

International Classification:

G01C 19/72
G01C 19/64
G01J 4/00

US Classification:

356465, 356364, 356459

Abstract:

An optical gyroscope is provided for measuring a small angular difference. The gyroscope includes a laser, a pre-selection polarizer, a first beam splitter, a coil of optical fiber, a second beam splitter, a post-selection polarizer, a spectrometer and an analyzer. The laser emits a pulse beam of coherent photons. The beam has pulse duration σ. The pre-selection polarizer pre-selects the photons, and the first beam splitter separates the photons by their horizontal |+ and vertical |− polarization eigenstates. These beams are launched into a fiber optical coil of radius r, which preserves polarization. The coil rotates by a difference rotation angle Δθ. The second beam splitter recombines the polarized photon beams as they exit the coil. The post-selection polarizer post-selects the photons. The spectrometer captures the post-selected photons and measures the associated frequency translation δω.

US Patent:

8619261, Dec 31, 2013

Filed:

Aug 24, 2011

Appl. No.:

13/199507

Inventors:

Allen D. Parks - Spotsylvania VA, US
Scott E. Spence - Fredericksburg VA, US

Assignee:

The United States of America as represented by the Secretary of the Navy - Washington DC

International Classification:

G01B 9/02

US Classification:

356450

Abstract:

A quantum dynamical non-locality device is provided for establishing a photon traveling along a path in a binary state. The device includes twin Mach-Zehnder interferometer (MZI), a shutter and a detector. The twin MZI includes first and second right-isosceles triangle prisms, corresponding first and second trombone mirrors, and corresponding first and second spacers. The prisms join at a beam-splitter interface. The mirrors reflect the photon by an offset substantially perpendicular to photon's travel direction. The spacers are respectively disposed between their respective prisms and mirrors to produce corresponding spatial gaps. The path through the prisms includes traversing spacers and gaps. The detector detects a quantum state of the photon after passing the prisms and the mirrors. The shutter switches to one of disposed within and removed therefrom the first gap.

US Patent:

20120314215, Dec 13, 2012

Filed:

Jul 6, 2011

Appl. No.:

13/135974

Inventors:

Allen D. Parks - Spotsylvania VA, US
Scott E. Spence - Fredericksburg VA, US

Assignee:

United States Government, as represented by the Secretary of the Navy - Arlington VA

International Classification:

G01J 4/00

US Classification:

356364

Abstract:

An apparatus is provided for determining a target wavelength λ of a target photon beam. The apparatus includes a photon emitter, a pre-selection polarizer, a prism composed of a Faraday medium, a post-selection polarizer, a detector and an analyzer. The photon emitter projects a monochromatic light beam at the target wavelength λ substantially parallel to a magnetic field having strength B. The target wavelength is offset from established wavelength λ′ as λ=λ′+Δλ by wavelength difference of Δλ

US Patent:

20130155411, Jun 20, 2013

Filed:

Feb 12, 2013

Appl. No.:

13/764796

Inventors:

United States Government as represented by the Secretary of the Navy - Arlington VA, US
Scott E. Spence - Fredericksburg VA, US

Assignee:

United States Government as represented by the Secretary of the Navy - Arlington VA

International Classification:

G02F 1/21

US Classification:

356450

Abstract:

A signal amplifier is provided via a triple Mach-Zehnder interferometer (MZI) apparatus for determining intensity distribution at either a first port or a second port by a photon from a source. The first and second ports correspond to respective first and second directions. The MZI apparatus includes four beam-splitters disposed co-linearly in parallel between the source and the ports, six parallel mirrors, and first and second path projectors. Three of these mirrors are displaced along the first direction from the beam-splitters, while the remaining mirrors are displaced along the second direction. The path projectors conduct weak measurement of a photon occupation number and are disposed between the second beam-splitter and an adjacent downstream mirror. The output port is disposed beyond the fourth beam-splitter in the first direction. The intensity distribution at the output port is positive in response to one of the first measurement being positive and the second measurement being negative.