Abstract: Apparatuses and methods are described for generating an optical signal in an optical network. The apparatus comprises at least a first and a second laser configured to generate a first or second series of optical pulses respectively and a polarization beam combiner (PBC). The PBC is configured to receive the first and second series of optical pulses. Each optical pulse in the first series of optical pulses is received with a first state of polarization (SOP), and each optical pulse in the second series of optical pulses is received with a second SOP. The first SOP and second SOP is orthogonal with respect to each other, and the PBC is further configured to combine the first and second series of optical pulses and to output an un-polarized optical signal. The un-polarized optical signal may help to reduce or mitigate nonlinear optical impairments caused by polarization of the optical signal.

Abstract: The disclosed systems, structures, and methods are directed to an optical communication system. The optical communication system comprising an optical node configured to receive a light signal, in which the light signal is received from a first optical path and a second optical path, and the optical node is further configured to determine a change in state of polarization (SOP) of the light signal received from the first optical path and the second optical path, a processing unit configured to determine if at least a portion of the first optical path and the second optical path has a/similar change in SOP.

Abstract: There is described a fiber-optic sensor for measuring a light signal from a fluorescible sample comprising heavy metal ions, for example. The fiber-optic sensor comprises an optical fiber having a side surface by which the light signal from the fluorescible sample is inputted. The optical fiber is corrugated to form at least two gratings on the side surface of the optical fiber. Each grating comprises periodically longitudinally spaced-apart valleys on the surface of the optical fiber, and is longitudinally spaced apart from any other grating of the at least two gratings.

Abstract: There is described a fiber-optic sensor for measuring a light signal from a fluorescible sample comprising heavy metal ions, for example. The fiber-optic sensor comprises an optical fiber having a side surface by which the light signal from the fluorescible sample is inputted. The optical fiber is corrugated to form at least two gratings on the side surface of the optical fiber. Each grating comprises periodically longitudinally spaced-apart valleys on the surface of the optical fiber, and is longitudinally spaced apart from any other grating of the at least two gratings.