McLaren, MRomero, JPadgett, MJRoux, FSForbes, A2014-06-172014-06-172013-09McLaren, M, Romero, J, Padgett, M.J, Roux, F.S and Forbes, A. 2013. Two-photon optics of Bessel-Gaussian modes. Physical Review A, vol. 88, pp 033818(1)-033818(8)1050-2947http://arxiv.org/pdf/1306.2767v1.pdfhttp://hdl.handle.net/10204/7474Copyright: 2013 American Physical Society. This is an Open Access journal. The journal authorizes the publication of the information herewith contained. Published in Physical Review A, vol. 88, pp 033818(1)-033818(8)In this paper we consider geometrical two-photon optics of Bessel-Gaussian modes generated in spontaneous parametric down-conversion of a Gaussian pump beam. We provide a general theoretical expression for the orbital angular momentum (OAM) spectrum and Schmidt number in this basis and show how this may be varied by control over the radial degree of freedom, a continuous parameter in Bessel-Gaussian modes. As a test we first implement a back-projection technique to classically predict, by experiment, the quantum correlations for Bessel-Gaussian modes produced by three holographic masks: a blazed axicon, a binary axicon, and a binary Bessel function. We then proceed to test the theory on the down-converted photons using the binary Bessel mask. We experimentally quantify the number of usable OAM modes and confirm the theoretical prediction of a flattening in the OAMspectrum and a concomitant increase in the OAM bandwidth. The results have implications for the control of dimensionality in quantum states.enBessel-Gaussian modesGaussian pump beamsLaser beamsTwo-photon opticsOrbital angular momentumOAMSchmidt numberArticleMcLaren, M., Romero, J., Padgett, M., Roux, F., & Forbes, A. (2013). Two-photon optics of Bessel-Gaussian modes. http://hdl.handle.net/10204/7474McLaren, M, J Romero, MJ Padgett, FS Roux, and A Forbes "Two-photon optics of Bessel-Gaussian modes." (2013) http://hdl.handle.net/10204/7474McLaren M, Romero J, Padgett M, Roux F, Forbes A. Two-photon optics of Bessel-Gaussian modes. 2013; http://hdl.handle.net/10204/7474.TY - Article AU - McLaren, M AU - Romero, J AU - Padgett, MJ AU - Roux, FS AU - Forbes, A AB - In this paper we consider geometrical two-photon optics of Bessel-Gaussian modes generated in spontaneous parametric down-conversion of a Gaussian pump beam. We provide a general theoretical expression for the orbital angular momentum (OAM) spectrum and Schmidt number in this basis and show how this may be varied by control over the radial degree of freedom, a continuous parameter in Bessel-Gaussian modes. As a test we first implement a back-projection technique to classically predict, by experiment, the quantum correlations for Bessel-Gaussian modes produced by three holographic masks: a blazed axicon, a binary axicon, and a binary Bessel function. We then proceed to test the theory on the down-converted photons using the binary Bessel mask. We experimentally quantify the number of usable OAM modes and confirm the theoretical prediction of a flattening in the OAMspectrum and a concomitant increase in the OAM bandwidth. The results have implications for the control of dimensionality in quantum states. DA - 2013-09 DB - ResearchSpace DP - CSIR KW - Bessel-Gaussian modes KW - Gaussian pump beams KW - Laser beams KW - Two-photon optics KW - Orbital angular momentum KW - OAM KW - Schmidt number LK - https://researchspace.csir.co.za PY - 2013 SM - 1050-2947 T1 - Two-photon optics of Bessel-Gaussian modes TI - Two-photon optics of Bessel-Gaussian modes UR - http://hdl.handle.net/10204/7474 ER -