volume | PIER Journals

Abstract

In this work we show a novel method based on a local two-port interferometer to distinguish the topological charge of radio-vortices at 30 GHz by using a small portion of the entire wavefront only. The experimental investigation of the amplitude and phase properties of the interference pattern with a pure Gaussian beam (l = 0) and a l = 1 radio vortex is carried out, and results are compared with the theory based on Laguerre-Gauss modes. Experiments were performed both with the interferometer and with single antenna to highlight the effective benefits of the interferometric approach, sensitive to the azimuthal phase of the vortex field. Method is also extendable at higher topological charges for applications to high-density millimetric communications.

1. Coullet, P., L. Gil, and F. Rocca, "Optical vortices," Opt. Commun., Vol. 73, 403-408, 1989.
doi:10.1016/0030-4018(89)90180-6 Google Scholar

2. Brambilla, M., L. A. Lugiato, V. Penna, F. Prati, C. Tamm, and C. O. Weiss, "Transverse laser patterns. II. Variational principle for pattern selection, spatial multistability, and laser hydrodynamics," Phys. Rev. A, Vol. 43, 5114, 1991.
doi:10.1103/PhysRevA.43.5114 Google Scholar

3. Bazhenov, V. Yu., M. V. Vasnetsov, and M. S. Soskin, "Laser beams with screw dislocations in the wavefronts," Pis'ma Zh. Eksp. Teor. Fiz., Vol. 52, 1037-1039, 1990. Google Scholar

4. Bazhenov, V. Yu., M. S. Soskin, and M. V. Vasnetsov, "Screw dislocations in light wavefronts," J. Mod. Optics, Vol. 39, 985-990, 1992.
doi:10.1080/09500349214551011 Google Scholar

5. Allen, L., M. W. Beijersbergen, R. J. C. Spreeuw, and J. P.Woerdman, "Orbital angular momentum of light and the transformation of Laguerre-Gaussian laser modes," Phys. Rev. A, Vol. 45, 8185, 1992.
doi:10.1103/PhysRevA.45.8185 Google Scholar

6. Willner, A. E., K. Panga, H. Song, K. Zou, and H. Zhou, "Orbital angular momentum of light for communications," Appl. Phys. Rev., Vol. 8, 041312, 2021.
doi:10.1063/5.0054885 Google Scholar

7. Willner, A. E., Y. Ren, G. Xie, Y. Yan, L. Li, Z. Zhao, J. Wang, M. Tur, A. F. Molisch, and S. Ashrafi, "Recent advances in high-capacity free-space optical and radio-frequency communications using orbital angular momentum multiplexing," Philos. Trans. A Math. Phy. Eng. Sci., Vol. 375, 20150439, 2017. Google Scholar

8. Cozzolino, D., D. Bacco, B. Da Lio, K. Ingerslev, Y. Ding, K. Dalgaard, P. Kristensen, M. Galili, K. Rottwitt, S. Ramachandran, and L. K. Oxenløwe, "Orbital angular momentum states enabling fiber-based high-dimensional quantum communication," Phys. Rev. App., Vol. 11, 064058, 2019.
doi:10.1103/PhysRevApplied.11.064058 Google Scholar

9. Wang, J., S. Chen, and J. Liu, "Orbital angular momentum communications based on standard multi-mode fiber," APL Photonics, Vol. 6, 060804, 2021.
doi:10.1063/5.0049022 Google Scholar

10. Ren, Y., L. Li, Z. Wang, et al. "Orbital angular momentum-based space division multiplexing for high-capacity underwater optical communications," Sci. Rep., Vol. 6, 33306, 2016.
doi:10.1038/srep33306 Google Scholar

11. Yan, Y., G. Xie, M. Lavery, et al. "High-capacity millimetre-wave communications with orbital angular momentum multiplexing," Nat. Commun., Vol. 5, 4876, 2014.
doi:10.1038/ncomms5876 Google Scholar

12. Hui, X., S. Zheng, Y. Chen, et al. "Multiplexed millimeter wave communication with dual Orbital Angular Momentum (OAM) mode antennas," Sci. Rep., Vol. 5, 10148, 2015.
doi:10.1038/srep10148 Google Scholar

13. Allen, B., D. Simmons, T. D. Drysdale, and J. Coon, "Performance analysis of an orbital angular momentum multiplexed amplify-and-forward radio relay chain with inter-modal crosstalk," R. Soc. Open Sci., Vol. 6, 181063, 2019.
doi:10.1098/rsos.181063 Google Scholar

14. Assimonis, S. D., M. A. B. Abbasi, and V. Fusco, "Millimeter-wave multi-mode circular antenna array for uni-cast multi-cast and OAM communication," Sci. Rep., Vol. 11, 4928, 2021.
doi:10.1038/s41598-021-83301-1 Google Scholar

15. Mirhosseini, M., M. Malik, Z. Shi, and R. W. Boyd, "Efficient separation of the orbital angular momentum eigenstates of light," Nat. Commun., Vol. 4, 2781, 2013.
doi:10.1038/ncomms3781 Google Scholar

16. Li, C. and S. Zhao, "Efficient separating orbital angular momentum mode with radial varying phase," Opt. Express, Vol. 5, 267-270, 2017. Google Scholar

17. Berkhout, G. C. G., M. P. J. Lavery, J. Courtial, M. W. Beijersbergen, and M. J. Padgett, "Efficient sorting of orbital angular momentum states of light," Phys. Rev. Lett., Vol. 105, 153601, 2010.
doi:10.1103/PhysRevLett.105.153601 Google Scholar

18. Paroli, B., A. Cirella, I. Drebot, V. Petrillo, M. Siano, and M. A. C. Potenza, "Asymmetric lateral coherence of OAM radiation reveals topological charge and local curvature," Journal of Optics, Vol. 20, 1-10, 2018.
doi:10.1088/2040-8986/aac936 Google Scholar

19. Paroli, B., M. Siano, and M. A. C. Potenza, "The local intrinsic curvature of wavefronts allows to detect optical vortices," Opt. Express, Vol. 27, 17550, 2019.
doi:10.1364/OE.27.017550 Google Scholar

20. Scalcinati, L., B. Paroli, M. Zannoni, and M. A. C. Potenza, "Measurement of the local intrinsic curvature of a l = 1 radio-vortex at 30 GHz," Progress In Electromagnetic Research M, Vol. 94, 1-8, 2020.
doi:10.2528/PIERM20041407 Google Scholar

21. Paroli, B., M. Siano, and M. A. C. Potenza, "Measuring the topological charge of orbital angular momentum radiation in single-shot by means of wavefront intrinsic curvature," Appl. Opt., Vol. 59, 5258, 2020.
doi:10.1364/AO.392341 Google Scholar

22. Paroli, B., M. Siano, and M. A. C. Potenza, "A composite beam of radiation with orbital angular momentum allows effective local, single-shot measurement of topological charge," Opt. Commun., Vol. 459, 2020.
doi:10.1016/j.optcom.2019.125049 Google Scholar

23. Paroli, B., M. Siano, and M. A. C. Potenza, "Dense-code free space transmission by local demultiplexing optical states of a composed vortex," Opt. Express, Vol. 29, 14412-14424, 2021.
doi:10.1364/OE.417772 Google Scholar

24. Koksal, K., M. Babiker, V. E. Lembessis, and J. Yuan, "Chirality and helicity of linearly-polarised Laguerre-Gaussian beams of small beam waists," Opt. Commun., Vol. 490, 126907, 2021.
doi:10.1016/j.optcom.2021.126907 Google Scholar

Mr. Lorenzo Scalcinati

Professor Bruno Paroli

Professor Mario Zannoni

Prof. Massimo Gervasi

Professor Marco Alberto Carlo Potenza