High-speed formation of persistent gratings in doped semiconductors

Summary form only given. We describe time-resolved measurements of optical grating formation in Te-doped AlGaAs. Local refractive index modulation resulting from spatially selective ionization of defect sites known as "DX" centers produces holographic diffraction gratings with efficiencies above 10% for grating periods as small as 135 nm. These gratings are persistent for a duration that ranges from microseconds to many years depending on the sample temperature--the longer times being available only at cryogenic temperatures thus far.