We present a protocol for performing entanglement swapping with intense<br> pulsed beams. In a first step, the generation of amplitude correlations<br> between two systems that have never interacted directly is demonstrated.<br> This is verified in direct detection with electronic modulation of the<br> detected photocurrents. The measured correlations are better than<br> expected from a classical reconstruction scheme. In an entanglement<br> swapping process, a four-partite entangled state is generated. We prove<br> experimentally that the amplitudes of the four optical modes are quantum<br> correlated 3 dB below shot noise, which is consistent with the presence<br> of genuine four-party entanglement.
Quantum interferometry with intense optical pulses
Gerd Leuchs,
Christine Silberhorn,
O Glockl,
Christoph Marquardt,
N Korolkova
FORTSCHRITTE DER PHYSIK-PROGRESS OF PHYSICS
51
(4-5)
409-413
(2003)
| Journal
For intense optical pulses the optical Kerr interaction in matter such<br> as an optical fiber is large enough to generate quantum states of light<br> with significant non-classical properties. On this basis pairs of<br> entangled light pulses have been generated. This entanglement can be<br> used for novel schemes in high precision interferometry and for quantum<br> communication protocols such as quantum dense coding.
Contact
Research Group Christoph Marquardt
Max Planck Institute for the Science of Light Staudtstr. 2 91058 Erlangen, Germany
