Boston Applied Technologies, Incorporated

Corning Applied Technologies Corporation

Other

Nz Applied Technologies Corp.

Nanjing Ioptron Scientific, Inc. Ltd.

Yingyin Kevin Zou

Hua Jiang

Feiling Wang

Qiushui Chen

Paul Melman

Kewen Kevin Li

Xiaomei Guo

Jing Zhao

Ning Xu

Hongzhi Zhao

Deshun Chen

Guanghai Jin

Dean Z Tsang

Xiao-Li Li

Run Zhang

Wei Hu

Jingwen Zhang

A monolithic multiferroic heterostructure fabricated using CSD (chemical solution deposition) is disclosed. The monolithic heterostructure includes a substrate, a ferromagnetic layer, a ferroelectric layer, and one or more seed layers that enhance crystallinity and promote high frequency performance.

Composition and method of making a monolithic heterostructure of multiferroic thin films

A nano-composite structure comprises of an amorphous matrix with embedded nano-crystallites. The nano-crystallites are precipitated from the amorphous matrix via heat treatment of a solution mixture of metal salts or metalorganic compounds to an appropriate temperature range and with a suitable duration, or heating of a mixture of non-crystalline compounds. The nano-crystallites are self-assembled in the amorphous matrix without forming agglomerates or distinguished grain boundaries. The nano-composite structure can be used for transparent display, transparent optical ceramics, protection armor, nuclear protection, pulsed power, high voltage electronics, high energy storage system and high power microwave systems.

Nano-composite structure and processes making of

A technique for equatorially mounting a telescope includes a right ascension support having a first end coupled to a counterweight assembly and a second end coupled to a declination support. The right ascension support is coupled to a base and extends downwardly and backwardly from the first end to the second end. The resulting arrangement causes the act of balancing the telescope about its right ascension axis also substantially to balance the telescope about its base.

Balanced equatorial mount technique for telescope

A polarization imaging apparatus measures the Stokes image of a sample. The apparatus consists of an optical lens set, a first variable phase retarder (VPR) with its optical axis aligned 22.5&#xb0;, a second variable phase retarder with its optical axis aligned 45&#xb0;, a linear polarizer, a imaging sensor for sensing the intensity images of the sample, a controller and a computer. Two variable phase retarders were controlled independently by a computer through a controller unit which generates a sequential of voltages to control the phase retardations of the first and second variable phase retarders. A auto-calibration procedure was incorporated into the polarization imaging apparatus to correct the misalignment of first and second VPRs, as well as the half-wave voltage of the VPRs. A set of four intensity images, I, I, Iand Iof the sample were captured by imaging sensor when the phase retardations of VPRs were set at (0,0), (&#x3c0;,0), (&#x3c0;,&#x3c0;) and (&#x3c0;/2,&#x3c0;), respectively. Then four Stokes components of a Stokes image, S, S, Sand Swere calculated using the four intensity images.

Polarization imaging apparatus with auto-calibration

A heterostructure of multiferroics or magnetoelectrics (ME) was disclosed. The film has both ferromagnetic and ferroelectric properties, as well as magneto-optic (MO) and electro-optic (EO) properties. Oxide buffer layers were employed to allow grown a cracking-free heterostructure a solution coating method.

Heterostructure of ferromagnetic and ferroelectric materials with magneto-optic and electro-optic effects

The present invention provides a rare-earth ions doped, especially erbium and ytterbium doped transparent electro-optic gain ceramic material consisting lead, zirconium, titanium and lanthanum. The electro-optic gain ceramic material either has a linear electro-optic coefficient or a quadratic electro-optic coefficient, which is greater than about 0.3&#xd7;10m/Vfor the latter, a propagation loss of less than about 0.3 dB/mm, and an optical gain of great than 1.5 dB/mm at a wavelength of about 1550 nm while optically pumped by a 1.4 watts diode laser at a wavelength of 970 nm at 20&#xb0; C. The present invention also provides electro-optic devices including a rare-earth ions doped, especially erbium and ytterbium doped, transparent electro-optic gain ceramic material consisting lead, zirconium, titanium and lanthanum. The present invention also provides lossless optical devices and amplifiers with an operating wavelength in the range of 1450 nm to 1700 nm while optically pumped at a wavelength in the range of 880 nm to 1020 nm. The materials and devices of the present invention are useful in light intensity, phase and polarization control at a wavelength of about 1550 nm.

Transparent electro-optic gain ceramics and devices

A polarization imaging apparatus measures the Stokes image of a sample. The apparatus consists of an optical lens set, a linear polarizerwith its optical axis, a first variable phase retarderwith its optical axisaligned 22.5&#xb0; to axis, a second variable phase retarderwith its optical axisaligned 45&#xb0; to axis, a imaging sensorfor sensing the intensity images of the sample, a controllerand a computer. Two variable phase retardersandwere controlled independently by a computerthrough a controller unitwhich generates a sequential of voltages to control the phase retardations of VPRsand. A set of four intensity images, I, I, Iand Iof the sample were captured by imaging sensorwhen the phase retardations of VPRsandwere set at (0,0), (&#x3c0;,0), (&#x3c0;,&#x3c0;) and (&#x3c0;/2,&#x3c0;), respectively Then four Stokes components of a Stokes image, S, S, Sand Swere calculated using the four intensity images.

Polarization imaging apparatus

An electro-optic Q-switch for generating sequence of laser pulses was disclosed. The Q-switch comprises a quadratic electro-optic material and is connected with an electronic unit generating a radio frequency wave with positive and negative pulses alternatively. The Q-switch is controlled by the radio frequency wave in such a way that laser pulse is generated when the radio frequency wave changes its polarity

Electro-optic Q-switch

An electrically controllable azimuth optical rotator ( ) includes a first quarterwave plate ( ) for receiving a first beam of electromagnetic energy ( ) having a first arbitrary polarization state, and outputting a second beam ( ) in response to the first quarterwave plate ( ). An electric voltage controlled ferro-electric variable phase retarder ( ) aligned at approximately 45 degrees to the first quarterwave plate ( ) receives the second beam and provides a third beam in response to the retarder ( ). The electric voltage controlled ferro-electric variable phase retarder ( ) is characterized by a phase shift of &phgr;&equals;2&agr;, where &agr; is a desired angle of rotation of the first arbitrary polarization state. To provide a voltage-controlled rotation, a second quarterwave plate ( ) is aligned either parallel or perpendicular to the first quarterwave plate ( ) for receiving the third beam ( ) and outputting a fourth beam ( ) in response to the retarder ( ). As a result, the fourth beam ( ) has a polarization state similar to the first arbitrary polarization state but rotated by &agr;.

Ferro-electric azimuth rotator

A polarization mode dispersion center ( ) measures PMD impairment through the cross-correlation of optical pulses. A second variable phase retarder plate ( ) is oriented with polarization eigenstates at preferably 45 degree angle with respect to those eigenstates of a first variable phase retarder plate ( ) to provide controllable phase retardations that can be varied and measured as an indication of PMD impairment.

Cross-correlating PMD detector

An apparatus and method for filtering an optical input is disclosed. In an illustrative embodiment, an optical input is split into polarization components along separate paths. The polarization components are then fed into a first electro-optic device that includes a set of electrodes across which a voltage is applied to adjust a wavelength transmission characteristic of the device. A section of the first device positioned between the electrodes preferably has a birefringence that is adjusted depending on the voltage applied across the electrodes. The adjusted components of the optical input are thereafter combined to produce an optical output. Accordingly, the optical input can be attenuated based on the voltage applied to electrodes of the first electro-optic device.

Dynamic optical filter

A polarization transformer includes at least one plate of transparent polycrystalline material which has an optical axis oriented perpendicular to a propagation direction of incident radiation having a first polarization state. The plate includes electrodes for applying an electric field across a plane of the plate perpendicular to the propagation direction so as to provide controlled phase change such that the polarization of radiation transmitted through the polarization transformer is transformed from the first polarization state to a second polarization state. The plate in a preferred embodiment comprises a ferroelectric complex oxide such as lead lanthanum zirconate titanate (PLZT) material. Such a material provides devices that have very fast response (on the order of microseconds) and low insertion loss.

Polarization transformer

The invention provides a fiber-optic 2&times;2 switch using a dual-fiber 50:50 input coupler and a dual-fiber 50:50 output coupler. One fiber from each coupler makes contact to an inner transparent electrode on a planar layer of electro-optic material and the other fibers make contact to an outer transparent electrode on the layer. The electro-optic layer has its other side coated with a transparent electrode which is placed in optical contact with one end of a GRIN lens. The fibers are arranged so that the inner fibers are at conjugate points and the outer fibers also at conjugate points of the lens. The other end of the lens is coated with a mirror. Applying a voltage between either the inner or outer electrode changes the optical path length for the light from and to the fibers traveling through the material under the selected electrode causing the light from the two input fibers to be switched between the two output fibers. 2&times;N switches can be constructed by concatenating 2&times;2 switches. The switch can also be used as a modulator. A convenient fiber alignment method is described.

High-speed low-loss fiber-optic switches

There is provided a device for use with fiber-optic cables for polarization insensitive amplitude modulation of light comprising a planar electro-optic layer with a reflective conductive mirror electrode on one side and a pair of transparent conductive electrodes on the other. The transparent conductive electrodes have a small separation along a straight line. A GRIN lens has one end in optical contact with the transparent conductive electrodes with its axis located over the line separating the electrodes. An input optical fiber and an output optical fiber are placed in optical contact with the other end of the lens at points which are symmetrically displaced from the axis of the lens. Light coming from input fiber is collimated by the GRIN lens and directed to the transparent electrodes, through the electro-optic layer and to the mirror from which it is reflected and refocused by the GRIN lens onto the output fiber. Applying a voltage between any of the transparent electrodes and the reflecting electrode changes the optical path length for half the beam so that when it is refocused on the output fiber, the two halves interfere constructively of destructively, depending on the change in path length. In one version, the electro-optic layer is a PLZT ceramic plate, while in others, it is a thick or thin film. In still other versions, two or more electro-optic layers are used in series in order to reduce the voltage required for the same optical path length change. A means to eliminate residual sensitivity to polarization sensitivity is described.

Growing community of inventors

Lexington, MA, United States of America

Yingyin Kevin Zou