An embodiment of the present invention relates to an optical element comprising a plurality of perturbing centers arranged in a scattering plane of the optical element. The optical element comprises at least two oriented groups of oriented perturbing centers, wherein a group-individual orientation is assigned to each oriented group, wherein the perturbing centers of each oriented group are oriented in accordance with the same group-individual orientation), and wherein the group-individual orientations are angled relatively to one another. The oriented groups are interweaved. Adjacent perturbing centers belong to different groups and are angled to each other.

A waveguide apparatus, comprises: disposed in at least one layer: an input coupler; a first fold grating; a second fold grating; an output coupler; and a source of light optically coupled to the waveguide providing at least first and second polarizations of the light and at least one wavelength. The input coupler is configured to cause the first polarization light to travel along a first total internal reflection (TIR) path and the second polarization light to travel along a second TIR path.

An integrated on-chip polarization rotator splitter (26) comprises a waveguide polarization rotator (54) having a first and a second layer (62) that form a rib waveguide (66) together and are both made of silicon nitride. The first layer (62) has a first, a second and a third section. The first layer (64) has a first width (w.sub.1) that increases in the first section (S1), is constant in the second section (S1) and decreases in the third section (S3). The second layer (64) has a second width (w.sub.2) that continuously increases. The polarization rotator splitter (26) further includes a waveguide polarization splitter (61) comprising a first strip waveguide (71) and a second strip waveguide (72) that are separated by a gap (74). The first and second strip waveguides (71, 72) are also made of silicon nitride. The first and second strip waveguide (71, 72) form an asymmetric evanescent direction coupler.

A terahertz polarization beam splitter based on a two-core negative curvature fiber is provided, which relates to the technical field of optical fiber communication. The polarization beam splitter includes: a base circular tube and core separation structures. Multiple large cladding tubes are internally tangent and connected to an inner wall of the base circular tube and arranged at equal intervals along a circumference of the inner wall of the base circular tube, and the multiple large cladding tubes are symmetrically distributed on the inner wall of the base circular tube. Embedded circular tubes are internally tangent and connected to inner walls of the multiple large cladding tubes respectively. The core separation structures are two in number.

An optical waveguide device includes first and second waveguides formed parallel to each other. The first waveguide includes a first rib and a first slab. The first slab is formed in a region between the first rib and the second waveguide. The second waveguide includes a second rib, a second slab and a third slab. The second rib is provided between the second slab and the third slab. The first and second slabs are integrally formed. At one end of the optical waveguide device, a first effective refractive index that indicates an effective refractive index of a TEi mode in the first waveguide is higher than a second effective refractive index that indicates an effective refractive index of a TEj mode in the second waveguide. At another end, the first effective refractive index is lower than the second effective refractive index.

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 (2×2OS). A first phase shifter (PS) is interfaced with either the first or second OW. Light is output from the first 2×2OS into a third OW and a fourth OW. Light within the third and fourth OW's is input to a second 2×2OS. A second PS is interfaced with either the third or fourth OW. Light is output from the second 2×2OS into a fifth OW for further processing.

The proposed technology allows for 1+1 optical protection and may improve coherent module output optical power by 3 dB over similar transmitter (Tx) and receiver (Rx) implementation complexity, as well as allow for integration into existing datacenter formats.

The present disclosure provides devices, systems, circuits, and effective methods for advanced optical applications using plasmonics and ENZ materials. The disclosure provides for enhancement of the optical tunability of phase and amplitude of propagating plasmons, nonlinear-optical effects, and resonant network in optical fiber tip nanocircuits and integrates the tunable plasmonic and ENZ effects for in-fiber applications to provide optical fiber with high operating speed and low power consumption. The invention yields efficient coupling of a plasmonic functional nanocircuit on the facet of an optical fiber core. The invention also can use gate-tunable ENZ materials to electrically and nonlinear optically tune the plasmonic nanocircuits for advanced light manipulation. The invention efficiently integrates and manipulates the voltage-tuned ENZ resonance for phase and amplitude modulation in optical fiber nanocircuits.

An optoelectronic chip includes optical inputs having different passbands, a photonic circuit to be tested, and an optical coupling device configured to couple said inputs to the photonic circuit to be tested.

An optical device for polarizing light including a polarization altering element operatively coupled to a light path associated with the first light coupling device and the second light coupling device is described. The optical device may further include a first waveguide portion including a first layer having parallel plane surfaces with the first waveguide portion having a first light coupling device. The optical device may also include a second waveguide portion including a second layer having parallel plane surfaces with the second waveguide portion having a second light coupling device.