The nonpolar m-plane ͑1100͒ thin film GaN and InGaN / GaN light-emitting diodes ͑LEDs͒ grown by metal-organic chemical vapor deposition on LiAlO 2 ͑100͒ substrates are reported. The LEDs emit green light with output power of 80 W under a direct current of 20 mA for a 400 ϫ 400 m 2 device. The current versus voltage ͑I-V͒ characteristic of the diode shows soft rectifying properties caused by defects and impurities in the p-n junction. The electroluminescence peak wavelength dependence on injection current, for currents in excess of 20 mA, saturates at 515-516 nm. This proves the absence of polarization fields in the active region present in c-plane structures. The light output intensity versus current ͑L-I͒ characteristic of the diode exhibits a superlinear relation at low injection current caused by nonradiative centers providing a shunt path and a linear light emission zone at high current level when these centers are saturated. © 2007 American Institute of Physics. ͓DOI: 10.1063/1.2825419͔ III-nitride materials provide great practical benefits in producing short wavelength light-emitting diodes ͑LEDs͒. These devices are conventionally grown on c-plane sapphire or SiC substrates, which suffer from the quantum-confined Stark effect. 1 The quantum efficiency decreases due to the spatial separation of the electron and hole wave functions within the quantum wells, thereby reducing recombination probability of electron-hole pairs, especially when the emission wavelength exceeds 500 nm. This is caused by the electrostatic fields along the ͓0001͔ axis of hexagonal III nitrides due to the spontaneous and piezoelectric polarizations. In contrast, the growth direction of optoelectronic devices normal to the direction of the polarization ͑e.g., growth along the a and m directions͒ is one promising way to avoid these polarization effects. Recently, significant progress has been made in the fabrication of nonpolar LEDs on r-plane sapphire 2 or on m-plane and a-plane freestanding GaN substrates. 3,4 The ␥-LiAlO 2 ͑100͒ substrate is another candidate substrate for growing m-plane GaN films. 5,6 The m-plane InGaN / GaN multiple quantum wells ͑MQWs͒ have been synthesizing substrates by molecular-beam epitaxy, 7 and nonpolar LED structures have been grown by metalorganic chemical vapor deposition ͑MOCVD͒ on LiAlO 2 ͑100͒. 8,9 However, the device performance of m-plane LEDs has still not been reported yet. In this letter, we report on the MOCVD growth of m-plane GaN thin film and nonpolar m-plane InGaN / GaN LEDs on LiAlO 2 ͑100͒ substrates. The electrical and optical properties of these structures are mentioned.The In x Ga 1−x N / GaN LED structures, shown in Fig. 1, were grown on LiAlO 2 ͑100͒ using a Thomas Swan MOCVD system which has a close-coupled-showerhead reactor. Epigrade trimethylgallium, Trimethylindium, and high-purity ammonia were used as the source precursors for In, Ga, and N, respectively. Silane ͑SiH 4 ͒ and bis͑cyclopentadienyl͒mag-nesium were used for n-and p-type dopings. Only nitrogen ͑N 2 ͒ was used as car...

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A 3.5 nm amorphous CoFeB film was sputtered on GaAs (001) wafer substrate without applying magnetic field during deposition, and a significant in-plane uniaxial magnetic anisotropy (UMA) field (Hu) of about 300 Oe could be achieved. To precisely determine the intrinsic Gilbert damping constant (α) of this film, both ferromagnetic resonance (FMR) and time-resolved magneto-optical Kerr effect (TRMOKE) techniques were utilized. With good fitting of the dynamic spectra of FMR and TRMOKE, α is calculated to be 0.010 and 0.013, respectively. Obviously, the latter is 30% larger than the former, which is due to the transient heating effect during the TRMOKE measurement. In comparison with ordinary amorphous CoFeB films with negligible magnetic anisotropies, α is enhanced significantly in the CoFeB/GaAs(001) film, which may be mainly resulted from the enhanced spin-orbit coupling induced by the CoFeB/GaAs interface. However, the significant in-plane UMA plays minor role in the enhancement of α.

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Background: In a Spanish Lung Cancer Group (SLCG) phase II trial, the combination of BRCA1 and receptor-associated protein 80 (RAP80) expression was significantly associated with outcome in Caucasian patients with nonsmall-cell lung cancer (NSCLC). The SLCG therefore undertook an industry-independent collaborative randomized phase III trial comparing nonselected cisplatin-based chemotherapy with therapy customized according to BRCA1/RAP80 expression. An analogous randomized phase II trial was carried out in China under the auspices of the SLCG to evaluate the effect of BRCA1/RAP80 expression in Asian patients.Patients and methods: Eligibility criteria included stage IIIB-IV NSCLC and sufficient tumor specimen for molecular analysis. Randomization to the control or experimental arm was 1 : 1 in the SLCG trial and 1 : 3 in the Chinese trial.