1-1hit |
Masakazu MORI Akiyuki TAKEDA Takeshi KAWAI Mari MIYATA Toshio GOTO Nobuhide YAMAGUCHI
The dependence of mode partition characteristics of 1.3 µm Fabry-Perot laser diodes on the modulation frequency and the modulation code has been investigated. From measurements with the frequency domain method and a simple analysis, it is confirmed that the modulation frequency dependence of k-value is caused by a competition among longitudinal modes which occurs with a time constant of several nano seconds. The mode partition characteristics in NRZ code is more affected by this mode competition than that in RZ code. Nevertheless, the k-value in NRZ code at modulation frequency fb is about the same as that in RZ code at modulation frequency fb/2. A simple formula which gives the k-value as a function of the modulation frequency is derived.