We demonstrate a self-electro-optic effect device (SEED) designed to work at 1047 nm to match the high power available from a Nd:YLF laser. The device uses a strain-balanced InGaAs/GaAs multiple quantum well grown on a GaAs substrate with an InGaAs buffer layer of linearly graded composition. It has improved performance compared to previous devices in this system. We have obtained a single pass modulation contrast ratio of 1.74 by applying 13-V reverse bias, and have found 99% photodetection quantum efficiency under the built-in junction field. Bistability in a resistor-SEED configuration is demonstrated.