Are on-chip heralded single photon sources possible by intermodal four wave mixing in silicon waveguides?

Are on-chip heralded single photon sources possible by intermodal four wave mixing in silicon waveguides? 

S. Signorini, S. Piccione, M. Ghulinyan, G. Pucker, L. Pavesi

Proc. of SPIE Vol. 10733

DOI: 10.1117/12.2320956

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