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A recently constructed cyclotron magnet at the Institute of Modern Physics of Chinese Academy of Sciences (IMPCAS) will be used as the injector of Heavy Ion Therapy Facility in Lanzhou (HITFiL). The diameter of the magnet is 2.92 m and its height is 1.52 m. The total weight of the magnet is 70 tons. The isochronous magnetic field for \q/m = 5/12 is achieved by appropriate pole edge profile. The paper discusses the various design and fabrication aspects of the magnet. The paper also presents the field measurement results and its comparison with simulation. [ABSTRACT FROM PUBLISHER]

Organic ultraviolet photodetectors (PDs) with a narrow-band spectral response are fabricated. TAPC and PBD were utilized as the electron donor and acceptor, respectively. Glass/indium tin oxide (ITO) was employed as the anode contact and the incident light window. The PDs reveal a narrow response width of 30 nm at 316–346 nm. A peak response of 0.12 A/W at 330 nm and a photo-to-dark ratio of about \1.1 \times \10^2 under 330-nm light illumination with an intensity of 0.95 \mW/cm^2 were achieved. The realization of the narrow-band response should be ascribed to the steep absorption of organic materials at the long wavelength and the blocking role of glass/ITO contact at the short wavelength. [ABSTRACT FROM AUTHOR]

Solar-blind photoresistors based on \Mg0.48\Zn0.52 \O thin films were fabricated on r-plane sapphire substrates by radio-frequency plasma-assisted molecular beam epitaxy. High-quality a-plane-orientation single-phase wurtzite \Mg0.48\Zn0.52\O thin films are demonstrated by X-ray diffraction and absorption spectra. The MgZnO photoresistors exhibit a large dark/photoresistance ratio up to \1.7 \times \10^4 with the light intensity of 0.61 \mW/cm^2 at 260 nm. The spectral response shows a sharp response peak only in the solar-blind region with maximum responsivity of \1.5 \times \10^-3\ \Omega^-1\cdot\W^-1 . [ABSTRACT FROM PUBLISHER]

Many normal conducting magnets are used in Heavy Ion Research Facility in Lanzhou (HIRFL) accelerator's magnet system at Institute of Modern Physics (IMP). The magnet design, fabrication and measurement of Cooling Storage Ring (CSR) are presented. All magnets are done with laminated and welded with 0.5 mm-thick steel sheets. For the dipole of CSR main ring (CSRm) an H type magnet was chosen with an air circle on the pole. For the CSR experimental ring (CSRe) a C type was chosen with an air circle and two air slots on the pole to improve the field homogeneity. All quadrupoles' endplates were made with punched pieces after coating epoxy glue. They were also chamfered directly on ends of the pole to reduce the 12th order contribution of magnetic field. Magnets design and fabrication for heavy ion therapy facility in Lanzhou (HITFiL) will be also described in this paper. Some superconducting magnets research at IMP will be reported too. A super-ferric dipole prototype of FAIR Super-FRS was built and it is been testing. The super-ferric dipole static and ramping magnetic field was measured in IMP. Two superconducting solenoids (3 T and 5 T magnetic field) with a \phi 70\ mm warm bore had been developed to calibrate Hall probe and high field testing, some testing results are reported. And a magnetic field of 7 T Penning Trap system is being developed for precise mass measurements. [ABSTRACT FROM PUBLISHER]

The superconducting magnet of the LPT (Lanzhou Penning trap) consists of nine coaxial coils. The maximum magnetic field is 7 T and thus results in a large magnetic force. In order to assure the mechanical stability, it is necessary to do the stress analysis of the magnet system. The 3D Finite Element Analysis of thermal and mechanical behavior was presented in this paper. For the numerical simulation and analysis of the phenomena inside the structure, the ADINA and TOSCA code were chosen right from start. The ADINA code is commonly used for numerical simulations of the structure analysis [1] and the TOSCA code is professional software to calculate the magnetic field and Lorentz Forces. The results of the analysis were evaluated in terms of the stress and deformation. [ABSTRACT FROM AUTHOR]

The Super-FRS (Super FRagment Separator) is a part of FAIR (Facility for Antiproton and Ion Research), which will be constructed at GSI, Germany by 17 countries. The Super-FRS comprises 24 superferric dipole magnets. The 2D and 3D magnetic field simulations of the prototype magnet are described in this paper. A passive trim slot and four chamfered removable poles are used to satisfy the required field homogeneity which is better than ±3 x 10-4 at 1.6 T, 0.8 T and 0.16 T in a wide elliptical useable aperture of 380 mm 140 mm. Measurement results at various field levels are shown in this paper as well. It can be seen from the comparison of calculation and measurement results that the magnetic designs of the magnet fulfils the requirements. [ABSTRACT FROM AUTHOR]

Some superconducting magnets research at IMP (Institute of Modern Physics, CAS, Lanzhou) will be described in this paper. Firstly, a superconducting electron cyclotron resonance ion source (SECRAL) was successfully built to produce intense beams of highly charged heavy ions for Heavy Ion Research Facility in Lanzhou (HIRFL). An innovation design of SECRAL is that the three axial solenoid coils are located inside of a sextupole bore in order to reduce the interaction forces between the sextupole coils and the solenoid coils. For 28 GHz operation, the magnet assembly can produce peak mirror fields on axis of 3.6 T at injection, 2.2 T at extraction, and a radial sextupole field of 2.0 T at plasma chamber wall. Some excellent results of ion beam intensity have been produced and SECRAL has been put into operation to provide highly charged ion beams for HIRFL since May 2007. Secondly, a super-ferric dipole prototype of FAIR Super-FRS is being built by FCG (FAIR China Group) in cooperation with GSI. Its superconducting coils and cryostat is made and tested in the Institute of Plasma Physics (IPP, Hefei), and it more 50 tons laminated yoke was made in IMP. This super-ferric dipole static magnetic field was measured in IMP, it reach to the design requirement, ramping field and other tests will be done in the future. Thirdly, a 3 T superconducting homogenous magnetic field solenoid with a Φ70 mm warm bore has been developed to calibrate Hall sensor, some testing results is reported. And a penning trap system called LPT (Lanzhou Penning Trap) is now being developed for precise mass measurements. [ABSTRACT FROM AUTHOR]

Co/Cu multilayer nanowires fabricated in an array using anodized aluminium oxide (AAO) template has been investigated. Experimental conditions are optimized to fabricate Co/Cu multilayer systems with fixed Cu and variable Co layer thicknesses. Magnetization reversal mode is found to depend on the Co layer thickness. A transition occurs from coherent rotation to a combination of coherent and curling rotation at around t(Co) = 60 nm with increasing t(Co). The reversal modes have been investigated using the magnetic hysteresis loops measured at room temperature for Co/Cu nanowires placed at various angles between the directions of the nanowire axis and external fields using a vibrating sample magnetometer. The magnetic easy axis changes from the direction perpendicular to nanowires to that parallel to the nanowires at around t(Co) = 60 nm, indicating a change in the magnetization reversal mode. The reversal mode for the nanowires with thin disk-shaped Co layers is of a coherent rotation type, while that for long rod-shaped Co layers can be explained by a combination of coherent rotation and a curling mode. [ABSTRACT FROM AUTHOR]

The magnet design, fabrication, and measurement of HIRFL-CSR (Heavy Ion Research Facility in Lanzhou Cooling Storage Ring) are presented. All magnets will be laminated and welded with an armor-coated surface between two big endplates made of sticking glue 0.5 mm-thick sheets. The dipole of CSRm was chosen an H type with an air circle on the pole to improve the field uniformity. The dipole of CSRe was chosen the C type with an air circle and two air slots on the pole to improve the field homogeneity. Its reproducibility of magnet to magnet was adjusted with inserting small laminating pieces before demountable pole ends to reach less than ±2 × 10-4 at optimized field level. CSRm quadrupoles diameter is 170 mm and has two different lengths, and its endplates were made with punching pieces after coating with epoxy glue, there is chamfered directly on the pole ends to reduce 12th-order contribution of field and without the demountable pole ends. CSRe main quadrupoles diameter is 240 mm and has two different lengths, and its endplates were also made with punching pieces coated with epoxy glue, there is also chamfered directly on the pole ends to reduce 12th-order contribution of field like CSRm. [ABSTRACT FROM AUTHOR]

High quality epitaxial thin films of FeSe1-xTe_x (x=0–1) have been successfully fabricated. Their superconducting transition temperatures are around 8–13 K. Microwave properties of a film (x=0.7) was studied by a sapphire dielectric cavity at 9.315 GHz. The cavity, which has a quality factor of 45000 in room temperature with TE011-mode, is specially designed for the measurement of small samples with the sapphire cylinder having a small hole in the center. Thin film samples with dimension of 1–2 mm can be put in the middle of the hole, supported by a very thin sapphire rod. The cavity is sealed in a vacuum chamber soaked in the liquid ^4He and the temperature of the thin sapphire rod (hence the sample) can be controlled from 1.6 K to 60 K with a stability about \pm1 mK. Temperature dependence of transmission response and Q-factors were measured by a network analyser (Agilent N5230C). The results showed a clear signature of multi-gap superconductivity. No evidences of existence of node in the energy gap were found as the normalized change in the surface reactance and the corresponding normalized change in the in-plane penetration depth have flat dependence at low temperatures. [ABSTRACT FROM AUTHOR]

The magnetic field (MF) annealing of dc electrodeposited ferromagnetic nanowire arrays of compositions Co94 Fe06, Co91 Fe07B2 was done in the direction of their easy axis of magnetization (in plane) at 265°C under 800 Oe applied magnetic field for 2 h. An induced magnetic anisotropy (MA) and a large increase in saturation magnetization (Ms) were manifested by the changes in hysteresis loops of the nanowire samples before and after the annealing process. The structural changes were investigated using X-ray diffraction and transmission electron microscopy (TEM). The shape of nanowires, the predicted natural texture with c-axis in the plane of membrane (because of high concentration of cobalt) and diffusional pair ordering of unlike atoms along the direction of external applied field were thought to be the causes of induced MA. The reannealing of samples in absence of MF at 400 °C and 600 °C produced no significant changes in hysteresis loops instead of removing the MA but with evolution of crystalline phase in both the samples. Therefore, the shape of nanowire was concluded to play the major role in persistence of induced MA in nanowire samples after high temperature annealing. [ABSTRACT FROM AUTHOR]