Quantum communications: Tetrat coding
Abstract
This work shows that an orthogonal tetrat basis element made up of two photons can be generated with two optical parametric down-converters and identified with a multiport detection system for coincidences. The transmission gain over the usual coding in bits is g=2. The information is assigned to each photon pair using a single conjugate beam of the parametric down-conversion. This system also demonstrates a way to get a pair of disentangled polarized photons by handling just one photon of an entangled pair.
- Publication:
-
Physical Review A
- Pub Date:
- October 1998
- DOI:
- 10.1103/PhysRevA.58.3332
- Bibcode:
- 1998PhRvA..58.3332B
- Keywords:
-
- 03.67.Hk;
- 42.50.Dv;
- 89.70.+c;
- Quantum communication;
- Nonclassical states of the electromagnetic field including entangled photon states;
- quantum state engineering and measurements;
- Information theory and communication theory