An electro-optical device is fabricated on a semiconductor-on-insulator (SOI) substrate. The electro-optical device comprises a silicon dioxide layer, and an active layer having ferroelectric properties on the silicon dioxide layer. The silicon dioxide layer includes a first silicon dioxide layer of the SOI substrate and a second silicon dioxide layer converted from a silicon layer of the SOI substrate. The active layer includes a buffer layer epitaxially grown on the silicon layer of the SOI substrate and a ferroelectric layer epitaxially grown on the buffer layer. The electro-optical device further comprises one or more additional layers over the active layer, and first and second contacts to the active layer through at least one of the one or more additional layers. Methods of fabricating the electro-optical device are also described herein.

An electro-optical device is fabricated on a semiconductor-on-insulator (SOI) substrate. The electro-optical device comprises a silicon dioxide layer, and an active layer having ferroelectric properties on the silicon dioxide layer. The silicon dioxide layer includes a first silicon dioxide layer of the SOI substrate and a second silicon dioxide layer converted from a silicon layer of the SOI substrate. The active layer includes a buffer layer epitaxially grown on the silicon layer of the SOI substrate and a ferroelectric layer epitaxially grown on the buffer layer. The electro-optical device further comprises one or more additional layers over the active layer, and first and second contacts to the active layer through at least one of the one or more additional layers. Methods of fabricating the electro-optical device are also described herein.

An optical device that includes at least one magnetic element including a first ferromagnetic layer, a second ferromagnetic layer, and a spacer layer sandwiched between the first ferromagnetic layer and the second ferromagnetic layer; a substrate; and a waveguide is provided, wherein the waveguide and the magnetic element are located on or above the substrate, and wherein at least some of light propagating in the waveguide is applied to the magnetic element.

An electro-optic device includes a substrate and a waveguide on the substrate. The waveguide includes a layer stack including a plurality of electro-optic material layers interleaved with a plurality of interlayers and a waveguide core adjacent to the layer stack. The waveguide may include a pair of electrodes in electrical contact with the plurality of electro-optic material layers. The plurality of interlayers maintains a first lattice structure at room temperature and a cryogenic temperature. The plurality of electro-optic material layers maintains a second lattice structure and crystallographic phase at the room temperature and the cryogenic temperature.

An optical device is described. At least a portion of the optical device includes ferroelectric non-linear optical material(s) and is fabricated utilizing ultraviolet lithography. In some aspects the at least the portion of the optical device is fabricated using deep ultraviolet lithography. In some aspects, the short range root mean square surface roughness of a sidewall of the at least the portion of the optical device is less than ten nanometers. In some aspects, the at least the portion of the optical device has a loss of not more than 2 dB/cm.

An electro-optic device includes a substrate and a waveguide on the substrate. The waveguide includes a layer stack including a plurality of electro-optic material layers interleaved with a plurality of interlayers, a waveguide core adjacent to the layer stack, a waveguide cladding layer, and a pair of electrodes in electrical contact with the plurality of electro-optic material layers. The plurality of interlayers maintains a first lattice structure at room temperature and a cryogenic temperature. The plurality of electro-optic material layers maintains a second lattice structure and crystallographic phase at the room temperature and the cryogenic temperature.

An optical phase shifter according to an embodiment for achieving the object of the present disclosure includes a first semiconductor layer formed on a substrate, a second semiconductor layer having opposite polarity to the first semiconductor layer, an insulating layer formed between the first semiconductor layer and the second semiconductor layer, and including ferroelectrics, a first electrode connected to the first semiconductor layer, and a second electrode connected to the second semiconductor layer. According to an embodiment, the introduction of ferroelectric materials to a semiconductor-insulator-semiconductor (SIS) optical phase shifter brings about improvement in charge collection efficiency resulting from the negative capacitance effect, thereby achieving higher phase modulation efficiency and lower power consumption. Additionally, it is possible to realize a new structure of optical switch or modulator device through design changes of the type of ferroelectrics and the structural variables.

A terahertz device includes a first waveguide, which is a plasmonic waveguide, having a first core with a nonlinear material, such as a ferroelectric material, and having a cladding with a first cladding portion including, at a first interface with the first core, a first cladding material that is an electrically conductive material. The terahertz device can include an antenna having a first and a second arm (for receiving or for emitting or for both, receiving and emitting electromagnetic waves in the terahertz range); a first and a second electrode arranged close to the first waveguide.

A terahertz device includes a first waveguide, which is a plasmonic waveguide, having a first core with a nonlinear material, such as a ferroelectric material, and having a cladding with a first cladding portion including, at a first interface with the first core, a first cladding material that is an electrically conductive material. The terahertz device can include an antenna having a first and a second arm (for receiving or for emitting or for both, receiving and emitting electromagnetic waves in the terahertz range); a first and a second electrode arranged close to the first waveguide.

An initial change and a secular change in an optical characteristic and a high frequency characteristic in a case where an optical modulator is mounted in a package of an optical transmission apparatus are suppressed while improving a space utilization rate in the package of the optical transmission apparatus. An optical modulator that is electrically connected to an electric circuit configured on a circuit board, includes a package that houses an optical modulation element, in which the package has, on a bottom surface facing the circuit board, a plurality of first protruding bodies protruding from the bottom surface.