A polarization controller comprising: (i) an optical fiber, and (ii) a carrier surrounding the optical fiber, the carrier comprising an off-center through hole with at least one collapsed region, such that the optical fiber is situated within the through hole and contacts the at least one collapsed region of the through hole, and the collapsed region exerts pressure on the optical fiber.

Photonic devices are disclosed including a first cladding layer, a first electrical contact comprising a first lead coupled to a first dielectric portion, a second electrical contact comprising a second lead coupled to a second dielectric portion, a waveguide structure comprising a slab layer comprising a first material, and a second cladding layer. The slab layer may be coupled to the first dielectric portion of the first electrical contact and the second dielectric portion of the second electrical contact. The first dielectric portion and the second dielectric portion may have a dielectric constant greater than a dielectric constant of the first material.

An optical fiber-mounted field sensor for measuring an electric or magnetic field includes an optical fiber configured to receive light from a laser source, a polarizer, a polarization manipulator, electro-optical material or magneto-optical material adjacent to the polarization manipulator, and a high reflection coating. The polarizer is adjacent to an output of the fiber, while the polarization manipulator is adjacent to the polarizer and opposite of the optical fiber. The electro-optical material or magneto-optical material is adjacent to the polarization manipulator, and the high reflection coating is adjacent to the electro-optical material or magneto-optical material. An optical mainframe for sending and receiving optical beams to and from the optical fiber-mounted field sensor is also described.

A polarization controller comprising: (i) an optical fiber, and (ii) a carrier surrounding the optical fiber, the carrier comprising an off-center through hole with at least one collapsed region, such that the optical fiber is situated within the through hole and contacts the at least one collapsed region of the through hole, and the collapsed region exerts pressure on the optical fiber.

Photonic devices are disclosed including a first cladding layer, a first electrical contact comprising a first lead coupled to a first dielectric portion, a second electrical contact comprising a second lead coupled to a second dielectric portion, a waveguide structure comprising a slab layer comprising a first material, and a second cladding layer. The slab layer may be coupled to the first dielectric portion of the first electrical contact and the second dielectric portion of the second electrical contact. The first dielectric portion and the second dielectric portion may have a dielectric constant greater than a dielectric constant of the first material.

It is provided a method for producing a polarization converter The method comprising the following steps: producing a first converter element which has a base side, an upper side extending parallel to the base side, and a longitudinal side oriented obliquely at an angle ε.sub.1 to the base side or a curved longitudinal side; producing a second converter element which has a base side, an upper side extending parallel to the base side, and a longitudinal side oriented obliquely at an angle ε.sub.2 to the base side or a curved longitudinal side; arranging the first and the second converter element in series in such a way that the obliquely oriented or curved longitudinal sides point in opposite directions.

An optical input polarization management device includes a polarization splitter and rotator (PSR) that directs a portion of incoming light having a first polarization through a first optical waveguide (OW). The PSR rotates a portion of the incoming light having a second polarization to the first polarization so as to provide polarization-rotated light. The PSR directs the polarization-rotated light through a second OW. Light within the first and second OW's is input to a first two-by-two optical splitter (2x2OS). A first phase shifter (PS) is interfaced with either the first or second OW. Light is output from the first 2x2OS into a third OW and a fourth OW. Light within the third and fourth OW's is input to a second 2x2OS. A second PS is interfaced with either the third or fourth OW. Light is output from the second 2x2OS into a fifth OW for further processing.

An electro-optic combiner includes a polarization splitter and rotator (PSR) that directs a portion of incoming light having a first polarization through a first optical waveguide (OW). The PSR rotates a portion of the incoming light having a second polarization to the first polarization to provide polarization-rotated light. The PSR directs the polarization-rotated light through a second OW. Each of the first and second OW's has a respective combiner section. The first and second OW combiner sections extend parallel to each other and have opposite light propagation directions. A plurality of ring resonators is disposed between the combiner sections of the first and second OW's and within an evanescent optically coupling distance of both the first and second OW's. Each of ring resonators operates at a respective resonant wavelength to optically couple light from the combiner section of the first OW into the combiner section of the second OW.

Various polarization rotator splitter (PRS) configurations are disclosed. In an example embodiment, a system includes a PRS that includes a silicon nitride (SiN) rib waveguide core that includes a rib and a ridge that extends vertically above the rib, the SiN rib waveguide core having a total height h.sub.SiN from a bottom of the rib to a top of the ridge, a rib height h.sub.rib from the bottom of the rib to a top of the rib, a rib width w.sub.rib, and a top width w.sub.SiN of the ridge. The rib width w.sub.rib varies along at least a portion of a length of the SiN rib waveguide core.

A lidar system includes a laser diode to provide a frequency modulated continuous wave (FMCW) signal, and a current source to provide a drive signal that modulates the laser diode. The current source is controlled to pre-distort the drive signal to provide a linear FMCW signal. The lidar system also includes a splitter to split the FMCW signal into an output signal and a local oscillator (LO) signal, a transmit coupler to transmit the output signal, a receive coupler to obtain a received signal based on reflection of the output signal by a target, and a combiner to combine the received signal with the LO signal into first and second combined signals. A first and second photodetector respectively receive the first and second combined signals and output first and second electrical signals from which a beat signal that indicates the pre-distortion needed for the drive signal is obtained.