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Two-wavelength switching with 1550 nm semiconductor laser amplifiers

Hurtado, A. and Adams, M. J. (2007) Two-wavelength switching with 1550 nm semiconductor laser amplifiers. Journal of Optical Networking, 6 (5). pp. 434-441. ISSN 1536-5379

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Two-wavelength switching operation between two signals at different wave-lengths is reported using the optical bistability occurring in two different semiconductor laser amplifiers. With this technique an optical signal can be set in either of the optical input wavelengths by appropriate choice of the powers of the input signals. Switching of a signal beam by another control beam at different wavelength is reported experimentally with a 1550 nm distributed feedback semiconductor optical amplifier. Also, a theoretical model has been generated to analyze the wavelength switching operation with a novel amplifier type - the 1550 nm vertical cavity semiconductor optical amplifier (VCSOA). Using a 1550 nm VCSOA, wavelength switching operation is reported with a calculated input power below 1 μW. This low input power requirement for switching added to the high-frequency response of the VCSOA, and the ease of fabricating 2D arrays of these devices due to the vertical structure, makes the VCSOA a very interesting device for use in optical switching applications in the optical telecommunication networks.