HIGH-SPEED SIGNAL WAVELENGTH CONVERSION USING A UNIDIRECTIONAL-OUTPUTWAVELENGTH CONVERSION DEVICE WITH ASYMMETRIC-KAPPA DBR STRUCTURE

The wavelength conversion device whose frequency response is evaluated analytically and experimentally in this work has a saturable absorber region, which acts as an optical gate, within the active region. The 3-dB bandwidth of this device was measured to be 800 MHz and found to be limited by the frequency response of the saturable absorber region. To speed up this device, the electrodes of the saturable absorber and the gain regions were connected electrically so that the device would act as a unidirectional-output distributed Bragg reflector (DBR) lase r. When the active region (saturable absorber and the gain regions) of this DBR laser were biased above threshold condition, the 3-dB bandwi dth was more than 10 GHz, and clear eye patterns were observed when th e input TM-polarized light intensity was modulated by a 10-Gbit/s pseu do-random NRZ signal. These results show that high-speed wavelength co nversion can be achieved when the device is operated as a laser diode.