The Advantages of Not Entangling Macroscopic Diamonds at Room Temperature
1Center for Optical Coherence Tomography and Modern Physics, Department of Orthopedic Surgery, Brigham and Women's Hospital, 75 Francis Street, MRB-114, Boston, MA 02115, USA; Center for Optical Coherence Tomography and Modern Physics, Department of Orthopedic Surgery, Harvard Medical School, 25 Shattuck Street, Boston, MA 02115, USA; Department of Electrical Engineering and Computer Science, Massachusetts Institute of Technology, Room 36-360, 77 Massachusetts Avenue, Cambridge, MA 02139, USA.
Abstract:
The recent paper entitled by K. C. Lee et al. (2011) establishes nonlocal macroscopic quantum correlations, which they term "entanglement", under ambient conditions. Photon(s)-phonon entanglements are established within each interferometer arm. However, our analysis demonstrates, the phonon fields between arms become correlated as a result of single-photon wavepacket path indistinguishability, not true nonlocal entanglement. We also note that a coherence expansion (as opposed to decoherence) resulted from local entanglement which was not recognized. It occurred from nearly identical Raman scattering in each arm (importantly not meeting the Born and Markovian approximations). The ability to establish nonlocal macroscopic quantum correlations through path indistinguishability rather than entanglement offers the opportunity to greatly expand quantum macroscopic theory and application, even though it was not true nonlocal entanglement.
