Key Laboratory of Polar Materials and Devices

Shanghai, China

Key Laboratory of Polar Materials and Devices

Shanghai, China
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Zhang C.,Beihang University | Yuan H.,Beihang University | Yuan H.,National Key Laboratory of Science and Technology on Reactor System Design Technology | Tang Z.,Key Laboratory of Polar Materials and Devices | And 4 more authors.
Applied Physics Reviews | Year: 2016

Rotation measurement in an inertial frame is an important technology for modern advanced navigation systems and fundamental physics research. Inertial rotation measurement with atomic spin has demonstrated potential in both high-precision applications and small-volume low-cost devices. After rapid development in the last few decades, atomic spin gyroscopes are considered a promising competitor to current conventional gyroscopes - from rate-grade to strategic-grade applications. Although it has been more than a century since the discovery of the relationship between atomic spin and mechanical rotation by Einstein [Naturwissenschaften, 3(19) (1915)], research on the coupling between spin and rotation is still a focus point. The semi-classical Larmor precession model is usually adopted to describe atomic spin gyroscope measurement principles. More recently, the geometric phase theory has provided a different view of the rotation measurement mechanism via atomic spin. The theory has been used to describe a gyroscope based on the nuclear spin ensembles in diamond. A comprehensive understanding of inertial rotation measurement principles based on atomic spin would be helpful for future applications. This work reviews different atomic spin gyroscopes and their rotation measurement principles with a historical overlook. In addition, the spin-rotation coupling mechanism in the context of the quantum phase theory is presented. The geometric phase is assumed to be the origin of the measurable rotation signal from atomic spins. In conclusion, with a complete understanding of inertial rotation measurements using atomic spin and advances in techniques, wide application of high-performance atomic spin gyroscopes is expected in the near future. © 2016 Author(s).


Yin W.,Key Laboratory of Polar Materials and Devices | Huang R.,Japan Fine Ceramics Center | Qi R.,Key Laboratory of Polar Materials and Devices | Duan C.,Ministry of EducationEast China Normal UniversityShanghai200062 China
Microscopy Research and Technique | Year: 2016

With the development of spherical aberration (Cs) corrected scanning transmission electron microscopy (STEM), high angle annular dark filed (HAADF) imaging technique has been widely applied in the microstructure characterization of various advanced materials with atomic resolution. However, current qualitative interpretation of the HAADF image is not enough to extract all the useful information. Here a modified peaks finding method was proposed to quantify the HAADF-STEM image to extract structural and chemical information. Firstly, an automatic segmentation technique including numerical filters and watershed algorithm was used to define the sub-areas for each atomic column. Then a 2D Gaussian fitting was carried out to determine the atomic column positions precisely, which provides the geometric information at the unit-cell scale. Furthermore, a self-adaptive integration based on the column position and the covariance of statistical Gaussian distribution were performed. The integrated intensities show very high sensitivity on the mean atomic number with improved signal-to-noise (S/N) ratio. Consequently, the polarization map and strain distributions were rebuilt from a HAADF-STEM image of the rhombohedral and tetragonal BiFeO3 interface and a MnO2 monolayer in LaAlO3/SrMnO3/SrTiO3 heterostructure was discerned from its neighbor TiO2 layers. © 2016 Wiley Periodicals, Inc.


Jing C.,Key Laboratory of Polar Materials and Devices | Guo H.,Key Laboratory of Polar Materials and Devices | Bai W.,Key Laboratory of Polar Materials and Devices | Hu Z.,Key Laboratory of Polar Materials and Devices | And 5 more authors.
Proceedings of SPIE - The International Society for Optical Engineering | Year: 2013

Ge99.04Mn0.96 thin film was fabricated by thermal evaporation of Mn doped GeO2 ceramic film under hydrogen atmosphere. Secondary phases were not detected by X-ray diffraction (XRD) and high resolution transmission electron microscopy (HRTEM) analyses. The film is p type. Room-temperature ferromagnetism was detected in the film. The ferromagnetic behavior may arise from alignment of the bound magnetic polarons (BMP) mediated by the localized holes in the system as well as ultra small secondary phases unable to be detected by XRD and HRTEM analyses. © 2013 SPIE.


Han H.L.,Shanghai Normal University | Liu A.Y.,Shanghai Normal University | Wei L.L.,Shanghai Normal University | Wang P.,Shanghai Normal University | And 3 more authors.
Proceedings of SPIE - The International Society for Optical Engineering | Year: 2013

Highly (222)-oriented 90%Pb(Zn1/3Nb2/3)O 3-10%PbTiO3(abbreviated PZN-PT) thin films, about 550nm in thickness, have been successfully grown on (111)Pt/Ti/SiO2/Si substrate by pulsed laser deposition method. Pure pyrochlore phase with highly (222)-preferred orientation, determined by X-ray diffraction, was formed in the PZN-PT thin films when the temperature of substrates is 550 °C. FE-SEM investigation shows that the surface appearance and the cross section of the films are smooth and crack-free with some dispersive spherical protrusions. The dielectric constant and loss of the thin films were measured using an impedance analyzer (HP4194A). The dielectric constant (εr) and the dissipation factor (tanδ) at 1 kHz are 205 and 0.03, respectively. © 2013 SPIE.


Jing C.,Key Laboratory of Polar Materials and Devices | Bai W.,Key Laboratory of Polar Materials and Devices | Hu Z.,Key Laboratory of Polar Materials and Devices | Yang P.,Key Laboratory of Polar Materials and Devices | And 4 more authors.
Progress in Biomedical Optics and Imaging - Proceedings of SPIE | Year: 2014

Attenuated total reflectance (ATR) infrared hollow waveguide attracts particular interest since it has both advantages of a hollow fiber and a light guiding mechanism similar to that of solid-core fibers. Presently, ATR hollow waveguides are mainly structured with single-crystal sapphire or glassy materials. These waveguides are somewhat brittle. More robust ATR hollow fibers are required in many military and domestic applications. In this work, ATR GeO2 hollow waveguides were prepared based on a copper capillary tube for transmitting CO2 laser light. The inner wall of the copper structural tube was polished using a high-pressure pulsed nanofluid technique. A hexagonal crystalline GeO2 reflective layer with sufficient thickness (>4 μm) was grown on the inner tube wall via a simple liquid phase deposition process at room temperature. The GeO2 coated copper hollow fiber exhibits a low-loss band within 10-11.5 μm. It can still be bent since the hollow-core size (1.4 mm) and the wall thickness (50 μm) are not too large. The transmissions of CO2 laser light are 91% and 43% under a straight condition and a 90° bend with a 30-cm radius condition, respectively. The waveguide displays high heat-resisting properties due to high thermal conductivity of the copper substrate tube and a high melting point (1115°C) of the GeO2 reflective layer. This work opens a door for low-temperature, low-cost growth of long ATR GeO2 infrared hollow fibers based on various substrate tubes, even including plastic capillary tubes. © 2014 SPIE.


Zhang J.,Key Laboratory of Polar Materials and Devices | Deng H.,Shanghai Research Institute of Materials | Yang P.,Key Laboratory of Polar Materials and Devices | He J.,Key Laboratory of Polar Materials and Devices | And 3 more authors.
Proceedings of SPIE - The International Society for Optical Engineering | Year: 2013

Ternary CuInSe2 (CIS) thin films were deposited on glass substrates using a binary CuIn alloy target and an elemental Cu target by employing radio-frequency (RF) magnetron sputtering process and post-selenization process. The selenization procedure is carried out within a partially close-spaced graphite box. The Cu content in CIS thin films can be controlled by different sputtering time of Cu target. The result of energy dispersive X-ray spectroscopy (EDX) indicated that the CIS thin film prepared by single CuIn alloys target had significantly composition deviation. Combined with the X-ray diffraction (XRD) and Raman spectra results showed that all CIS thin films have chalcopyrite structure. Further transmission spectra demonstrated that the optical band gap of CIS thin film is about 1.0 eV. © 2013 SPIE.


Lou X.,Key Laboratory of Polar Materials and Devices | Xu S.,Key Laboratory of Polar Materials and Devices | Zhu Y.,Key Laboratory of Polar Materials and Devices | Wang L.,Key Laboratory of Polar Materials and Devices | And 2 more authors.
Proceedings of SPIE - The International Society for Optical Engineering | Year: 2013

By combining a SnO2 thin film with silicon dioxide microchannel plate (SiO2-MCP), a three-dimensional (3D) structure with enough space to accommodate the volume change of SnO2 during charging-discharging is produced by MEMS and electroless deposition. Owing to the special structure of the MCP, the battery is able to deliver a reversible Li storage capacity of 408 mAhg-1 after 100 cycles. If the current density is reduced to 200 mAg-1 at a constant current during charging and discharging, the battery exhibits reversible capacities of 1575 and 996 mAhg-1 in the first discharging and charging cycle, respectively. However, a reversible Li-storage capacity of only 298 mAhg-1 is obtained after 50 cycles of deep charging at a current of 200 mAg-1. It is found that silicon is involved in the charging-discharging process at a low current. © 2013 SPIE.


Miao F.,Key Laboratory of Polar Materials and Devices | Miao F.,Qiqihar University | Tao B.,Key Laboratory of Polar Materials and Devices | Tao B.,Qiqihar University | And 5 more authors.
Journal of Power Sources | Year: 2010

A novel anode structure based on the three-dimensional silicon microchannel plates (Si-MCP) is proposed for direct methanol fuel cells (DMFCs). Ni-Pd nanoparticles produced by electroless plating onto the Si-MCP inner sidewalls and followed by annealing at 300 °C under argon serve as the catalyst. In order to evaluate the electroactivity of the nanocomposites, Ni-Pd/silicon composites synthesized by the same method are compared. Scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), and electrochemical methods are employed to investigate the Ni-Pd/Si-MCP anode materials. As a result of the synergetic effects rendered by the MCP and Ni-Pd nanoparticles, the Ni-Pd/Si-MCP nanocomposites exhibit superior electrocatalytic properties towards methanol electro-oxidation in alkaline solutions, as manifested by the negative onset potential and strong current response to methanol even during long-term cyclical oxidation of methanol. This new structure possesses unique and significant advantages such as low cost and integratability with silicon-based devices. © 2009 Elsevier B.V. All rights reserved.


Xu J.,Key Laboratory of Polar Materials and Devices | Yu K.,Key Laboratory of Polar Materials and Devices | Zhu Z.,Key Laboratory of Polar Materials and Devices
Physica E: Low-Dimensional Systems and Nanostructures | Year: 2010

Cu dendritic nanostructures were synthesized on ITO glass substructure by electrochemical deposition. SEM images showed that these Cu dendritic nanostuctures revealed a clear and well-defined dendritic fractal structure with a pronounced trunk and highly ordered branches distributed on both sides of the trunk. The diffusion-limited aggregation (DLA) model was used to explain the fractal growth of Cu dendritic nanostructures. Field emission properties of these Cu dendritic nanostructures were measured, which have possessed good performance with the turn-on field of 7.5 V/μm (defined as the electric field required to be detected at a current density of 0.1 mA/cm2) and the field enhancement factor β of 1094. © 2009 Elsevier B.V. All rights reserved.


Sun Y.,Key Laboratory of Polar Materials and Devices | Yang P.,Key Laboratory of Polar Materials and Devices | Chen Y.,Key Laboratory of Polar Materials and Devices | Shang L.,Key Laboratory of Polar Materials and Devices | Chu J.,Key Laboratory of Polar Materials and Devices
Optoelectronics and Advanced Materials, Rapid Communications | Year: 2012

Recently, incorporation of band-gap graded structure into CdTe absorption layer has been proposed for CdTe based solar cells. In the present work, we numerically investigate the effects of band-gap gradation on photovoltaic characteristics for CdS/CdZnTe band-gap back graded solar cells. Dependences of short circuit current density, open circuit voltage, and conversion efficiency on the grading strength are obtained and analyzed. Moreover, impacts of minority carrier diffusion length of band-gap graded CdZnTe layer on the grading benefits for CdS/CdZnTe back graded solar cells are discussed in detail.

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