S. Ohno et al., BISTABLE POLARIZATION SWITCHING IN TRANSVERSE MAGNETIC WAVE-INJECTED SEMICONDUCTOR-LASERS BY MODE HOPPING, Electronics & communications in Japan. Part 2, Electronics, 79(8), 1996, pp. 1-11
Bistable optical switching, which is applicable to optical memory, is
a key technology for the optical information-processing system. This p
aper describes the polarization switching of a semiconductor laser who
se normal and inverted output could be obtained simultaneously. This b
istability is realized by utilizing a semiconductor laser with bistabl
e mode-hopping characteristics (master laser) and injecting the TM pol
arization output of this laser into another semiconductor laser (slave
laser) constantly biased to the oscillation threshold. It is proposed
and confirmed by experiment that, by assuming these two lasers as one
optical system, bistable polarization switching can be obtained betwe
en the injection current of the system and the output polarization of
the system. First, as the principle of this polarization switching, th
e dependence of the injected light wavelength on amplification index o
f a semiconductor laser amplifier is explained. Then, the control of o
utput polarization by TM wave injection and mode hopping of a laser is
explained and the bistable characteristics of this optical system are
discussed from experimental and simulation viewpoints based on these
principles. The advantages of this bistable polarization switching are
pointed out theoretically and experimentally, and the intensity diffe
rence of the ON/OFF output and the rotation direction of the bistable
loop can be set according to the characteristics of the master and the
slave laser. Moreover, the possibility of multislave connection is co
njectured.