| Abstract: | An optical set-reset (SR) latch is formed from a first electroabsorption
modulator (EAM), a second EAM and a waveguide photodetector (PD) which
are arranged in an optical and electrical feedback loop which controls
the transmission of light through the first EAM to latch the first EAM in
a light-transmissive state in response to a Set light input. A second
waveguide PD controls the transmission of light through the second EAM
and is used to switch the first EAM to a light-absorptive state in
response to a Reset light input provided to the second waveguide PD. The
optical SR latch, which may be formed on a III-V compound semiconductor
substrate (e.g. an InP or a GaAs substrate) as a photonic integrated
circuit (PIC), stores a bit of optical information and has an optical
output for the logic state of that bit of information. |