  The silicon trackers of the ATLAS experiment at LHC (CERN) use optical links
for data transmission. VCSEL arrays operating at 850 nm are used to transmit
optical signals while PIN arrays are used to convert the optical signals into
electrical signals. We investigate the feasibility of using the devices at the
Super LHC (SLHC). We irradiated VCSEL and GaAs PIN arrays from three vendors
and silicon PIN arrays from one vendor. All arrays can be operated up to the
SLHC dosage except the GaAs PIN arrays which have very low responsivities after
irradiation and hence are probably not suitable for the SLHC application.
