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Capable of continuous at room temperatures, a blue-green semiconductor laser uses a 523 nm oscillation wavelength and offers a 4.5 mA threshold current. In developing the device, the engineers used zinc-magnesium-selenide for the photo layer, and zinc-magnesium-sulfide-selenide for the cladding layer. This encloses the electrons, the positive hole and the light. For this purpose, the engineers improved the proprietary manufacturing technique for the cladding layer, a process offering fine quality. A resonator surface protection film enhances the energy efficiency, enabling a suitable threshold current and a threshold current density of 1.4 kA/cm2.
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The engineers improved the proprietary manufacturing technique ________.