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A dual-wavelength laser source monolithically integrated with an isolator and a Y-junction coupler is fabricated by using a new quantum-well intermixing technique. The technique employs a buried Ge layer between the sample surface and the spin-on silica film to control the bandgap tuning in selective areas across a wafer. The integrated isolator can avoid the crosstalk between the two channels of the device. Two distinct lasing wavelengths of 950 and 969 nm are coupled into one single output port through the transparent Y-junction coupler. The two channels have similar threshold current and slope efficiency. [ABSTRACT FROM PUBLISHER]

Presents a study which investigated the tunneling magnetoresistance effect (TMR) of iron-lead-oxygen (Fe-Pb-O) granular films from different annealing time. Experimental details; Results of the study.

Investigates the magneto-transport properties of the granular solids with various film thickness. Experiments on the granular films; Findings and analysis of results; Conclusions.

Ultrafine Gd particles in a Cu metallic matrix have been obtained by post-annealing of as-sputtered metastable Gd/sub x/Cu/sub 1-x/ alloys at temperatures higher than 250/spl deg/C. The results of resistivity measurements show that the resistivities of as-sputtered metastable Gd/sub 0.2/Cu/sub 0.8/ and Gd/sub 0.3/Cu/sub 0.7/ alloys exhibit a resistivity minimum at low temperatures, an indication of the Kondo effect. In addition the temperature of the resistivity minimum rises with the increasing Gd content. Conversely, the resistivity of films after formation of Gd granules levels off at low temperatures. The magnetic results indicate that the metastable GdCu alloys are essentially a spin-glass at low temperature with the transition temperatures at around 3.5/spl sim/5 K. However, magnetization data at 80 K shows that the as-sputtered samples contain some small Gd ferromagnetic clusters in the paramagnetic matrix. The magnetic particles of granular films begin to be thermally blocked at T/sub B/ and become magnetically ordered below T/sub B/. Due to larger grain sizes, T/sub B/ is much higher for x=0.3 than for 0.2. The variation of transport and magnetic properties for samples with different annealing processes are described in detail. [ABSTRACT FROM PUBLISHER]