Large Quantum imaging of nonlocal spatial correlations induced by   orbital angular momentum
  Through scanned coincidence counting, we probe the quantum image produced by parametric down conversion with a pump beam carrying orbital angular momentum. Nonlocal spatial correlations are manifested through splitting of the coincidence spot into two. 
Adam R. Altman, Kahraman G. K\"opr\"ul\"u, Eric Corndorf, Prem Kumar,   and Geraldo A. Barbosa