Abstract: Provided in accordance with the herein described exemplary embodiments are piezo micro-machined ultrasonic transducers (pMUTs) each having a first electrode that includes a first electrode portion and a second electrode portion. The second electrode portion is separately operable from the first electrode portion. A second electrode is spaced apart from the first electrode and defines a space between the first electrode and the second electrode. A piezoelectric material is disposed in the space. Also provided are arrays of pMUTs wherein individual pMUTs have first electrode portions operably associated with array rows and second electrode portions operably associated with array columns.

Abstract: In this work is presented a method for fabrication of high-aspect ratio structures through spalling effect. The spalling is achieved through lithography, etching and sputtering processes, thus providing the flexibility to position the spalled structures according to the application requirements. This method has been successfully demonstrated for metal-oxides and metals. The width of the fabricated structures is dependent on the thickness of the film deposited by sputtering, where structures as small as 20 nm in width have been obtained.

Abstract: Structures for a wavelength-division multiplexing filter and methods of forming a structure for a wavelength-division multiplexing filter. A waveguide core of the wavelength-division multiplexing filter includes a first bend having a first curvature and a second bend having a second curvature different than the first curvature. The structure further includes a waveguide core region having a first end surface, a second end surface, and a bend arranged between the first and second end surfaces. The bend is positioned over the first bend of the waveguide core in an overlapping relationship.

Abstract: Structures for a wavelength-division multiplexing filter and methods of forming a structure for a wavelength-division multiplexing filter. A waveguide core of the wavelength-division multiplexing filter includes a first bend having a first curvature and a second bend having a second curvature different than the first curvature. The structure further includes a waveguide core region having a first end surface, a second end surface, and a bend arranged between the first and second end surfaces. The bend is positioned over the first bend of the waveguide core in an overlapping relationship.

Abstract: A fiber-optic salinity and temperature measurement includes a first Fabry-Perot interferometer and a second Fabry-Perot interferometer. Each of the Fabry-Perot interferometers includes a first optical fiber fusion spliced to a second optical fiber such that a relatively large cavity is formed between the fibers. The relatively large cavity forms the measurement chamber for each Fabry-Perot interferometer. The input port on each of the Fabry-Perot interferometers is coupled to an optical splitter such that a single optical signal input is provided to each Fabry-Perot interferometer. The output port on each of the Fabry-Perot interferometers is coupled to an optical combiner that combines the interference signal received from each of the Fabry-Perot interferometers. An optical signal analyzer coupled to an output port of the optical combiner determines the salinity and temperature of a sample material in the large cavity of the second Fabry-Perot interferometer.

Abstract: Structures for a polarizer and methods of fabricating a structure for a polarizer. A waveguide crossing includes a first arm and a second arm. A waveguide loop couples the first arm of the waveguide crossing to the second arm of the waveguide crossing. The waveguide crossing and the waveguide loop provide a structure for the polarizer.

Abstract: In this work is presented a method for fabrication of high-aspect ratio structures through spalling effect. The spalling is achieved through lithography, etching and sputtering processes, thus providing the flexibility to position the spalled structures according to the application requirements. This method has been successfully demonstrated for metal-oxides and metals. The width of the fabricated structures is dependent on the thickness of the film deposited by sputtering, where structures as small as 20 nm in width have been obtained.

Abstract: Structures for an optical power splitter and methods of forming a structure for an optical power splitter. A first waveguide core provides an input port, and second and third waveguide cores provide respective output ports. A non-linear waveguide taper is coupled to the first waveguide core at a first interface and is coupled to the second and third waveguide cores at a second interface. The non-linear waveguide taper includes a first curved section having a first width dimension that increases with increasing longitudinal distance from the first interface. The non-linear waveguide taper includes a second curved section having a second width dimension that increases with increasing longitudinal distance from the second interface. The first and second curved sections join at a longitudinal location at which the first and second width dimensions are each equal to a maximum width of the non-linear waveguide taper.

Abstract: Structures for a polarizer and methods of fabricating a structure for a polarizer. A waveguide crossing includes a first arm and a second arm. A waveguide loop couples the first arm of the waveguide crossing to the second arm of the waveguide crossing. The waveguide crossing and the waveguide loop provide a structure for the polarizer.

Abstract: Structures for a wavelength-division multiplexing filter and methods of fabricating a structure for a wavelength-division multiplexing filter. The structure includes a first waveguide core, a second waveguide core laterally spaced from the first waveguide core, and a ring resonator arranged in a vertical direction over the first waveguide core and the second waveguide core. The ring resonator is also arranged in a lateral direction between the first waveguide core and the second waveguide core. The first and second waveguide cores are composed of a semiconductor material, such as single-crystal silicon, and the ring resonator is composed of a dielectric material, such as silicon nitride.

Abstract: Structures for a wavelength-division multiplexing filter and methods of fabricating a structure for a wavelength-division multiplexing filter. The structure includes a first waveguide core, a second waveguide core laterally spaced from the first waveguide core, and a ring resonator arranged in a vertical direction over the first waveguide core and the second waveguide core. The ring resonator is also arranged in a lateral direction between the first waveguide core and the second waveguide core. The first and second waveguide cores are composed of a semiconductor material, such as single-crystal silicon, and the ring resonator is composed of a dielectric material, such as silicon nitride.

Abstract: A fiber-optic salinity and temperature measurement includes a first Fabry-Perot interferometer and a second Fabry-Perot interferometer. Each of the Fabry-Perot interferometers includes a first optical fiber fusion spliced to a second optical fiber such that a relatively large cavity is formed between the fibers. The relatively large cavity forms the measurement chamber for each Fabry-Perot interferometer. The input port on each of the Fabry-Perot interferometers is coupled to an optical splitter such that a single optical signal input is provided to each Fabry-Perot interferometer. The output port on each of the Fabry-Perot interferometers is coupled to an optical combiner that combines the interference signal received from each of the Fabry-Perot interferometers. An optical signal analyzer coupled to an output port of the optical combiner determines the salinity and temperature of a sample material in the large cavity of the second Fabry-Perot interferometer.

Abstract: An ultrasonic transducer and a method for a transmitting an acoustic wave using an ultrasonic transducer comprising a membrane; two or more patterned top electrodes; a pMUT array, wherein the patterned top electrode is arranged as row pin selector and column selector in an N×N array; the pMUT array having N+N electrical contacts; a single unpatterned bottom electrode; a row and column where the electrode is at equal or opposite polarities; and a AC driving voltage is applied to top electrodes with a phase difference of zero or is applied to one electrode to transmit the ultrasonic wave.

Abstract: Provided in accordance with the herein described exemplary embodiments are piezo micro-machined ultrasonic transducers (pMUTs) each having a first electrode that includes a first electrode portion and a second electrode portion. The second electrode portion is separately operable from the first electrode portion. A second electrode is spaced apart from the first electrode and defines a space between the first electrode and the second electrode. A piezoelectric material is disposed in the space. Also provided are arrays of pMUTs wherein individual pMUTs have first electrode portions operably associated with array rows and second electrode portions operably associated with array columns.