Orbital Angular Momentum Modes of High-Gain Parametric Down-Conversion

L. Beltran, G. Frascella, A. M. Perez, R. Fickler, P. R. Sharapova, M. Manceau, O. V. Tikhonova, R. W. Boyd, G. Leuchs, and M. V. Chekhova, J. Opt. 19, 044005 (2017).

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