Entangled images from four-wave mixing.
Two beams of light can be quantum mechanically entangled through correlations of their phase and intensity fluctuations. For a pair of spatially extended image-carrying light fields, the concept of entanglement can be applied not only to the entire images but also to their smaller details. We used a spatially multimode amplifier based on four-wave mixing in a hot vapor to produce twin images that exhibit localized entanglement. The images can be bright fields that display position-dependent quantum noise reduction in their intensity difference or vacuum twin beams that are strongly entangled when projected onto a large range of different spatial modes. The high degree of spatial entanglement demonstrates that the system is an ideal source for parallel continuous-variable quantum information protocols.
Joint Quantum Institute, National Institute of Standards and Technology, University of Maryland, Gaithersburg, MD 20899, USA. vincent.boyer@nist.gov
Vincent
V
Boyer
Alberto M
AM
Marino
Raphael C
RC
Pooser
Paul D
PD
Lett