Based on our original idea about monolithic integration of the superlumines
cent diode (SLD) with a semiconductor optical amplifier (SOA), the axis of
the current injection area was tilted. High superluminescent power (more th
an 200 mW) at 1.5 mum was obtained by optimizing the tilted device structur
e. No lasing mode was discovered within the range of measurement. In additi
on, it was discovered that the tilted integrated device had the function of
lasing suppression, to some extent.