Abstract

We experimentally demonstrate simultaneous turbulence mitigation and channel demultiplexing in a 200 Gbit/s orbital-angular-momentum (OAM) multiplexed link by adaptive wavefront shaping and diffusing (WSD) the light beams. Different realizations of two emulated turbulence strengths (the Fried parameter ${r_0} = 0.4,\,1.0\;{\rm mm}$) are mitigated. The experimental results show the following. (1) Crosstalk between OAM $l = + 1$ and $l = - 1$ modes can be reduced by $ {\gt} {10.0}$ and $ {\gt} {5.8}\;{\rm dB}$, respectively, under the weaker turbulence (${r_0} = 1.0\;{\rm mm}$); crosstalk is further improved by $ {\gt} {17.7}$ and $ {\gt} {19.4}\;{\rm dB}$, respectively, under most realizations in the stronger turbulence (${r_0} = 0.4\;{\rm mm}$). (2) The optical signal-to-noise ratio penalties for the bit error rate performance are measured to be ${\sim}{0.7}$ and ${\sim}{1.6}\;{\rm dB}$ under weaker turbulence, while measured to be ${\sim}{3.2}$ and ${\sim}{1.8}\;{\rm dB}$ under stronger turbulence for OAM $l = + 1$ and $l = - 1$ mode, respectively.

© 2020 Optical Society of America

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