Photon generating apparatus

Patent metadata

Field	Value
Publication number	US-10027426-B2
Application number	US-201715711174-A
Country	US
Kind code	B2
Filing date	Sep 21, 2017
Priority date	Nov 18, 2016
Publication date	Jul 17, 2018
Grant date	Jul 17, 2018

Abstract

According to one embodiment of the present invention, there is provided a photon generating apparatus including: a light source configured to emit light; an optical medium configured to generate a pair of photons from the light; a detector configured to detect one photon from the pair of photons and output a detection time of the photon; a buffer including an optical line and an optical switch disposed on an optical path of the photon, which is one photon except for the photon detected by the detector, of the pair of photons; and a processor configured to output a driving signal which controls the optical switch so that a delay occurs at the optical path using the detection time of the photon detected by the detector.

First claim

What is claimed is:

1. A photon generating apparatus comprising:
a light source configured to emit light;
an optical medium configured to generate a pair of photons from the light;
a detector configured to detect one photon from the pair of photons and output a detection time of the photon;
a buffer including an optical line and an optical switch disposed on an optical path of the photon, which is one photon except for the photon detected by the detector, of the pair of photons; and
a processor configured to output a driving signal which controls the optical switch so that a delay occurs at the optical path using the detection time of the photon detected by the detector;
wherein the optical switch includes a plurality of inputs and a plurality of outputs which are internally connected to the plurality of inputs;
wherein the optical line includes a first optical delay line disposed between at least one among the plurality of inputs and at least one among the plurality of outputs,
wherein a chromatic dispersion of the first optical delay line is removed.

2. The photon generating apparatus of claim 1 , wherein:
the light is emitted at a predetermined period; and
the first optical delay line is formed such that the photon, which is one photon except for the photon detected by the detector, of the pair of photons is delayed for an integral multiple of the period.

3. The photon generating apparatus of claim 2 , wherein the first optical delay line includes a plurality of optical fibers.

4. The photon generating apparatus of claim 3 , wherein the plurality of optical fibers have different lengths or chromatic dispersions.

5. The photon generating apparatus of claim 1 , wherein the driving signal forms an optical path configured to compensate for a value difference between the detection time of the photon detected by the detector and a preset time so that the photon, which is one photon except for the photon detected by the detector, of the pair of photons is output at the preset time.

6. The photon generating apparatus of claim 1 , wherein the optical medium performs one of spontaneous parametric down conversion and spontaneous four wave mixing.

7. The photon generating apparatus of claim 1 , wherein:
a plurality of optical switches each identical to the optical switch are included; and
wherein the optical line includes a second optical delay line disposed between the plurality of optical switches,
wherein a chromatic dispersion of the second optical delay line is removed.

8. The photon generating apparatus of claim 7 ,
wherein the second optical delay line is disposed between one output and one input of one of the plurality of the optical switches.

Assignees

• Korea Res Inst Standards & Sci

Inventors

• Park Hee Su
• Lee Eun Joo
• Lee Hee Jung
• Lee Sang Min

Classifications

• H04B10/70 Primary

  Photonic quantum communication · CPC title

• H04B10/2507

  for the reduction or elimination of distortion or dispersion · CPC title

• H04B10/2912

  characterised by the medium used for amplification or processing · CPC title

• H04B10/503

  Laser transmitters · CPC title

• H04B10/6161

  Compensation of chromatic dispersion · CPC title