Tekehiro Fukushima

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We fabricated the AlGaAs/GaAs 3QW quasi-stadium laser diodes with two-electrodes and succeeded in controlling directional laser emission by applying different currents to each electrode. We showed the ratio of laser emission with two different directions is proportional to the ratio of currents injected into two electrodes. These devices are applicable for(More)
We have proposed a new three-dimensional (3D) integration technology based on a chip-to-wafer bonding method which is called a super chip integration technology. Various kinds of chips such as processor chip, memory chips, analog IC chip and sensor chips which are fabricated by different technologies can be vertically stacked into a 3D LSI chip by using a(More)
Mode switching operation of multi-electrode strained InGaAsP multiple-quantum-well quasi-stadium laser diodes is reported. Far-field patterns exhibit highly directional emission along the laser cavity axis for current injection at the axis electrode and highly directional emission at angles plusmn19deg from the cavity axis for current injection at the ring(More)
A vibration-control mechanism for beams and columns was presented in our previous report in which the earthquake force was transformed into a vibration-control force by using a gear train mechanism. In our previous report, however, only the principle of transforming the earthquake force into the control force was presented; the discussion for real(More)
We investigate the lasing characteristics of oval-resonator laser diodes made of AlGaAs/GaAs quantum wells both experimentally and theoretically. The resonator shapes are various oval geometries, thereby probing chaotic and mixed classical dynamics. The far field pattern shows a pronounced fine structure that strongly depends on the cavity shape
In order to demonstrate controlling directional emissions corresponding to the ring trajectory modes by using external optical injection, we fabricate the AlGaAs/GaAs single-quantum-well tandem quasi-stadium laser diodes consist of the front slave and the rear master laser diodes. The geometry of the laser cavities have been defined by using a lithography(More)