Surface Acoustic Wave Induced Birefringence in In0.21Ga0.79As-GaAs Multiple Quantum Wells for Optical Modulation ≈1000 nm under Normal Incidence

摘要: This paper presents observation of quantum Confined Stark effect induced by the surface acoustic waves (SAW) propagating in multiple well (MQW) layers. It also evidence for first time SAW birefringence under normal mode operation MQWs. MQW layers usually do not exhibit significant when light is normally incident. The launching In0.21Ga0.79As-GaAs produces significantly different strain along direction propagation (y) as compared to lateral (x), and this turn results differential absorption coefficient Δα (= αx - αy) (Δnbir). enhanced due excitonic depends on magnitude RF power exciting transducer. An interdigitated transducer operating at 119 MHz with an aperture (w) wavelength (Λ) ratio 25 was used launch waves. Typical values Δn are range 0.01-0.02 polarized ≈1.01 μm varied between 0.5-1.2 Watt. Computations agreement experimental data. induces a perpendicular component Ez electric field which conventional producing index changes MQWs that vary function power.