Abstract:
There is provided a lithium niobate modulator structure (30) for mitigating DC bias drift comprising a highly doped semiconductor layer (44, 54) patterned above an optical waveguide (34) having one or more DC sections (38, 40) and an RF section (42), wherein a metal layer or contact (50) is in contact with a portion of the semiconductor layer (44, 54) and a buffer layer (46) is deposited in the RF section (42). There is also provided a method of making a lithium niobate electro-optical modulator having the aforementioned structure.
Abstract:
Disclosed herein is a digital electro-optical switch (1) comprising: - an electro-optical substrate (3); - a Y-shaped optical waveguide (2) formed in the substrate (3) and including an input branch (4) configured to be connected to an input optical waveguide, and two output branches (5) configured to be connected to respective output optical waveguides; and - electrically conductive electrodes (6, 7) formed on the substrate (3) and including an inner electrode (7) arranged between the output branches (5), substantially at a branching area of the optical waveguide (2), and two outer electrodes (6) arranged outside the output branches (5), on opposite sides of the inner electrode (7), the outer electrodes (6) being electrically operable to make the electro-optical switch (1) operative between a first switching state wherein transmission of optical energy is enhanced between the input branch (4) and a first one of the output branches (5), and substantially inhibited in a second one of the output branches (5), and a second switching state wherein transmission of optical energy is enhanced between the input branch (4) and the second output branch (5), and substantially inhibited in the first output branch (5); and - an optically transparent, electrically conductive film (9) arranged between each electrode (6, 7) and the substrate (3).
Abstract:
Electro-optic waveguide devices are disclosed that includes (a) an electro-optic polymer core and (b) at least one additional polymer clad or polymer buffer clad. Several embodiments comprise an electro-optic polymer core (35), a first polymer clad (40) in proximity to the electro-optic polymer core, a first polymer buffer clad (50) in proximity to the first polymer clad, and a second polymer clad (45) in proximity to the electro-optic polymer core. Another embodiment comprises an electro-optic polymer core and a polymer buffer clad (55). Another embodiment, wherein the polymer buffer clad comprises an organically modified sol-gel. Additionally, a method for fabricating polymer waveguide devices is disclosed.
Abstract:
An optical waveguide device including an electro-optical crystal substrate (10) having a top surface and a bottom surface; an optical waveguide path (14a, 14b) formed within a surface of the electro-optical crystal substrate; at least one electrode (12a, 12b, 13) positioned above the optical waveguide path for applying an electric field to the optical waveguide path; and a silicon titanium oxynitride layer (16) and a connecting layer (17) for interconnecting the silicon titanium oxynitride layer to another surface of the electro-optical crystal substrate that is opposite to the surface in which the optical waveguide path is formed.
Abstract:
An optical waveguide is formed on a substrate of a material having an electro-optic effect. An intermediate layer is formed on a major surface thereof. A metal-mounted polarizer is provided on the intermediate layer above the optical waveguide. A signal electrode and a grounding electrode are formed on the substrate or a buffer layer. The intermediate layer is made of a dielectric having a composition AO>x 2 y z x>1, 0>y>3, 0>z>2) In another mode, an optical waveguide and buffer layer are formed on a substrate of a material having an electro-optic effect, the buffer layer is partly removed by nonreactive dry-etching to form a first opening, a metal-mounted polarizer is formed in the first opening, and a signal electrode serving as a modulating electrode and a grounding electrode are formed on the buffer layer.
Abstract translation:在具有电光效应的材料的基板上形成光波导。 在其主表面上形成中间层。 在光波导上方的中间层上设置金属安装的偏振器。 在基板或缓冲层上形成信号电极和接地电极。 中间层由具有组成AO> x <,B> 2 和CO> z <的电介质(其中X表示二价元素,Y是三价元素,Z是四价元素,O氧 ,0> x> 1,0> y> 3,0> z> 2)在另一种模式中,在具有电光效应的材料的衬底上形成光波导和缓冲层,缓冲层部分 通过非反应性干蚀刻去除以形成第一开口,在第一开口中形成金属安装的偏振器,并且在缓冲层上形成用作调制电极的信号电极和接地电极。
Abstract:
The present invention relates to an optical component, such as, for example, a Mach-Zehnder modulator, in which the ground electrodes are formed directly on a surface of a substrate, that is, without the intermediary of conventional buffer layers. Forming the optical component without a dielectric layer between the ground electrodes and the substrate allows a reduction in the voltage required to drive a modulator, such as, for example, V pi , to be realised.
Abstract:
A method for fabricating ion exchange waveguides, such as lithium niobate or lithium tantalate waveguides in optical modulators includes ion exchanging the crystalline substrate (102) with a source of ions and annealing the substrate by pressurizing a gas atmosphere containing the lithium niobate or lithium tantalate substrate above normal atmospheric pressure, heating the substrate to a temperature ranging from about 150 degrees Celsius to about 1000 degrees Celsius, maintaining pressure and temperature to effect greater ion diffusion and limit exchange, and cooling the structure to an ambient temperature at an appropriate ramp down rate. In another aspect of the invention a powder (110) of the same chemical composition as the crystalline substrate (102) is introduced into the anneal process chamber (100) to limit the crystalline substrate from outgassing alkaline earth metal oxide during the anneal period. In yet another aspect of the invention an anneal container (100) is provided that allows for crystalline substrates (102) to be annealed in the presence of powder (110) without contaminating the substrate with the powder during the anneal process. Waveguides manufactured in accordance with the method exhibit superior drift performance.
Abstract:
An electro-optic device such as a Mach-Zehnder interferometer that includes a lithium niobate substrate having an optical waveguide that is formed in an upper surface of the substrate is described. The device includes a polymer buffer layer formed on the upper surface of the substrate. The polymer may be non-conductive or conductive. An electrode is formed on an upper surface of the buffer layer and is positioned to receive an RF signal that induces an electrical field in the optical waveguide. A conductive charge bleed-off layer may be formed between the buffer layer and the electrode in order to bleed-off pyroelectric charge. A semiconductor charge bleed-off layer may be formed between the substrate and the buffer layer.
Abstract:
An improved high-speed external optical modulator (10), modulated by RF waves, which velocity matches the RF waves with the optical waves is disclosed. The apparatus includes a lithium niobate substrate (16) on which is formed an optical waveguide (18, 20), electrically floating electrodes (32, 33, 34), a low dielectric buffer layer (30) and electrodes carrying the modulated RF energy (22, 24). At least one floating electrode (32, 33, 34) may comprise a series of spaced electrode segments for enhanced performance at high frequencies.