Measurements are reported of the electro‐optic properties of multiple‐quantum‐wellp‐i‐ndiodes at wavelengths where the waveguide propagation losses are small, 55–110 meV below the exciton resonance. Electroabsorptive and electrorefractive properties were measured as a function of polarization and crystal propagation direction. The electroabsorption and electrorefraction data show that there is a wavelength bandwidth of ∼25 nm where the quadratic electro‐optic coefficient is large (1–7×10−15cm2/V2) and the magnitude of the electroabsorption is <0.5 dB/mm for applied fields of up to 1×105V/cm. Compact, high‐dynamic‐range interferometric modulators can be realized in this wavelength band.