An electro-optic modulator comprising at least one nanodisordered potassium tantalate niobate crystal; first and second conductors operatively connected to the nanodisordered potassium tantalate niobate crystal adapted to be connected to a voltage source to modulate light passing there through; whereby light is modulated by passing through the nanodisordered potassium tantalate niobate crystal. A method for modulating light comprising providing at least one at least one nanodisordered potassium tantalate niobate crystal; providing first and second conductors operatively connected to the nanodisordered potassium tantalate niobate crystal adapted to be connected to a voltage source to modulate light passing there through; providing an interrogating light beam striking at least one nanodisordered potassium tantalate niobate crystal; modulating light passing through the nanodisordered potassium tantalate niobate crystal; and receiving a modulated light beam.

To effectively prevent the acceleration of the drift phenomenon generated by the application of a high electric field to a substrate through a bias electrode in a waveguide type optical element. A waveguide type optical element includes a substrate (100) having an electro-optic effect, two optical waveguides (104 and 106) disposed on a surface of the substrate, a non-conductive layer (120) which is disposed on the substrate and is made of a material having a lower dielectric constant than the substrate, and a control electrode (150) which is disposed on the non-conductive layer and is intended to generate a refractive index difference between the two optical waveguides by respectively applying electric fields to the two optical waveguides, and the non-conductive layer is constituted of a material which includes silicon oxide, an oxide of indium, and an oxide of titanium and has a ratio between a molar concentration of the titanium oxide and a molar concentration of indium oxide of 1.2 or more, and a voltage generating an electric field of 1 V/μm or more in the substrate is applied to the control electrode.

An optical phase modulator comprises a cascaded array of optical resonators, wherein each of the optical resonators has an input port and an output port. A plurality of waveguides are coupled between the optical resonators and are configured to provide cascaded optical communication between the optical resonators. Each of the waveguides is respectively coupled between the output port of one optical resonator and the input port of an adjacent optical resonator. A transmission electrode is positioned adjacent to the optical resonators, with the transmission electrode configured to apply a drive voltage across the optical resonators. The optical phase modulator is operative to co-propagate an input optical wave with the drive voltage, such that a resonator-to-resonator optical delay is matched with a resonator-to-resonator electrical delay.

Provided is an optical waveguide device in which both signal electrode collapse and signal electrode peeling/damage can be prevented. An optical waveguide device in which an optical waveguide is formed on a substrate and a control electrode for controlling a light wave propagating through the optical waveguide is disposed on the substrate, is characterized in that, the control electrode includes a signal electrode, and the signal electrode has a narrow portion, where a width of the signal electrode on a substrate side is narrow, and a wide portion, where a width of the signal electrode on an upper portion side of the signal electrode is wide, a prevention film that is disposed in contact with the narrow portion of the signal electrode and that prevents the signal electrode from collapsing, is provided on the substrate, and at a position of the signal electrode where the narrow portion and the wide portion are connected, a surface of the prevention film is formed as a curved surface protruding toward the signal electrode, and a side surface of the signal electrode is formed along the curved surface.

A high-power electro-optic modulator (EOM) is formed to use specialized electrodes of a material selected to have a CTE that matches the CTE of the modulator's crystal. Providing CTE matching reduces the presence of stress-induced birefringence, which is known to cause unwanted modulation of the propagating optical signal. The specialized electrodes are preferably formed of a CuW metal matrix composite having a W/Cu ratio selected to create the matching CTE value. Advantageously, the CuW-based electrodes also exhibit a thermal conductivity about an order of magnitude greater than conventional electrode material (brass, Kovar) and thus provide additional thermal stability to the EOM's performance.

An electro-optic modulator includes an optical structure and an electrical structure. The optical structure includes an input waveguide, a beam splitter, a first waveguide arm, a second waveguide arm, a beam combiner, and an output waveguide; each of the first waveguide arm and the second waveguide arm includes a conventional waveguide region. The first waveguide arm further includes a first modulating region, a second modulating region, and a third modulating region. The second waveguide arm further includes a fourth modulating region, a fifth modulating region, and a sixth modulating region; the electrical structure includes a traveling wave electrode including a signal-ground-signal electrode structure. The traveling wave electrode further includes a signal input region, a modulating electrode region, and a matched resistor region. The modulating electrode region includes a first signal electrode, a ground electrode, and a second signal electrode.

An optical waveguide device includes a substrate on which an intermediate layer, a thin-film LN layer of lithium niobate, and a buffer layer are stacked; an optical waveguide formed in the thin-film LN layer; and a plurality of electrodes near the optical waveguide. The intermediate layer and the buffer layer contain a same material of a metal element of any one of group 3 of group 18 of a periodic table of elements.

An optical waveguide device has a substrate, an intermediate layer, a thin-film LN layer containing an X-cut lithium niobate, and a buffer layer stacked on the substrate, and an optical waveguide having a ridge shape formed in the thin-film LN layer. The optical waveguide device includes a plurality of electrodes provided, respectively, at a first side and a second side of the optical waveguide. The electrodes are disposed so that respective bottom surfaces thereof are at positions lower than a position of a surface of the buffer layer.

An optical device includes an X-cut substrate, and a first waveguide and a second waveguide each being formed on the substrate and having a folding structure. The optical device includes a first signal electrode to generate a first electric field, and a second signal electrode to generate a second electric field with a reverse phase as compared to the first field. The first waveguide includes a first waveguide on an outward side to which the first field is applied from the first signal electrode, and a first waveguide on a return side to which the second field is applied from the second signal electrode. The second waveguide includes a second waveguide on the outward side to which the first field is applied from the first signal electrode, and a second waveguide on the return side to which the second field is applied from the second signal electrode.

A method includes receiving light at a light input of an electro-optic modulator device. The method includes directing the light via the light input into optical waveguides in an optical layer of an electro-optic modulator of the electro-optic modulator device. The method includes receiving a signal at an electric input of the electro-optic modulator device. The electric input is associated with an input impedance. The method includes providing the signal to an electrode structure of the electro-optic modulator. The electrode structure generates an electrical field based on the signal. The electric field modulates light in the optical waveguides to produce modulated light based on the signal. The electrode structure includes a constant impedance section associated with a second impedance less than the input impedance. The method also includes providing the modulated light based on the signal from the optical layer to one or more output optic fibers.