Quantum illumination with Gaussian states.
An optical transmitter irradiates a target region containing a bright thermal-noise bath in which a low-reflectivity object might be embedded. The light received from this region is used to decide whether the object is present or absent. The performance achieved using a coherent-state transmitter is compared with that of a quantum-illumination transmitter, i.e., one that employs the signal beam obtained from spontaneous parametric down-conversion. By making the optimum joint measurement on the light received from the target region together with the retained spontaneous parametric down-conversion idler beam, the quantum-illumination system realizes a 6 dB advantage in the error-probability exponent over the optimum reception coherent-state system. This advantage accrues despite there being no entanglement between the light collected from the target region and the retained idler beam.
Tan
Si-Hui
SH
Department of Physics, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA.
Erkmen
Baris I
BI
Giovannetti
Vittorio
V
Guha
Saikat
S
Lloyd
Seth
S
Maccone
Lorenzo
L
Pirandola
Stefano
S
Shapiro
Jeffrey H
JH