Reconfigurable 2 × 2 orbital angular momentum based optical switching of 50-Gbaud QPSK channels

We experimentally demonstrate a reconfigurable 2 × 2 switch for orbital angular momentum (OAM) multiplexed data-carrying optical beams. The switch can be configured to operate in either 'cross' or 'bar' state for each of the input OAM-multiplexed channels. The switching operation is demonstrated by operating the switch in five different configurations for the four OAM-multiplexed 50 Gbaud QPSK channels. An OSNR penalty < 2.5 dB is observed for the switched beams.