No-Go Theorem for Gaussian Quantum Error Correction
Abstract
We prove that Gaussian operations are of no use for protecting Gaussian states against Gaussian errors in quantum communication protocols. Specifically, we introduce a new quantity characterizing any single-mode Gaussian channel, called entanglement degradation, and show that it cannot decrease via Gaussian encoding and decoding operations only. The strength of this no-go theorem is illustrated with some examples of Gaussian channels.
- Publication:
-
Physical Review Letters
- Pub Date:
- March 2009
- DOI:
- 10.1103/PhysRevLett.102.120501
- arXiv:
- arXiv:0811.3128
- Bibcode:
- 2009PhRvL.102l0501N
- Keywords:
-
- 03.67.Pp;
- 42.50.Dv;
- Quantum error correction and other methods for protection against decoherence;
- Nonclassical states of the electromagnetic field including entangled photon states;
- quantum state engineering and measurements;
- Quantum Physics
- E-Print:
- 4 pages, 2 figures, REVTeX4