II–VI quantum confined Stark effect waveguide modulators

Abstract

Quantum confined Stark effect p-i-n waveguide modulators, grown on GaAs substrates by molecular beam epitaxy and using an undoped ZnSe/ZnCdSe multiquantum well structure as the guiding layer, have exhibited intensity modulation at wavelengths of 496 and 501 nm with extinction ratios of 6 and 4, respectively. These same devices have also demonstrated a transverse linear electro-optic effect observed as a superimposed secondary effect on the lateral intensity modulation at 514 nm in the form of phase modulation in the output of the same device. Intensity modulation has also been observed in quaternary laser waveguide structures, indicating that this is a device structure which is suitable for monolithic integration.

ZnSe-based electro-optic waveguide modulators for the blue-green spectral range

“…The development of ZnSe-based laser diodes operating continuously at room temperature has opened the need for material-compatible passive devices such as waveguide modulators and switches, suitable for monolithic integration. One way to achieve this goal is the utilization of the absorption change induced by an external electric field in the vicinity of the fundamental edge (Stark effect, Franz-Keldysh effect) [1][2][3][4][5]. When waveguide devices are considered, heat production, throughput and a very limited wavelength window represent serious problems in the electroabsorption regime.…”

The Stark effect of excitons in corrugated lateral surface superlattices: the effect of centre-of-mass quantization

“…Voltage-tunable infrared photodetectors making use of the large Stark shifts of the strong intersubband absorptions in coupled QWs have been proposed [5]. And very recently, waveguide modulators based on the QCSE in II-VI semiconductor multi-QWs were fabricated [6][7][8]; this work was motivated by their potential for monolithic integration with room-temperature II-VI semiconductor lasers operating in the blue/green spectral region. Investigations on the QCSE in different low-dimensional systems, such as quantum wires [9] and dots [10], are being carried out in searching for systems with more adjustable parameters for controlling the QCSE according to one's application requirements.…”

The strong Stark effect of intersubband transitions in corrugated lateral surface superlattices

“…Voltage-tunable infrared photodetectors making use of the large Stark shifts of the strong intersubband absorptions in coupled QWs have been proposed [5]. And very recently, waveguide modulators based on the QCSE in II-VI semiconductor multi-QWs were fabricated [6][7][8]; the motivation for this development was their potential for monolithic integration with room-temperature II-VI semiconductor lasers operating in the blue/green spectral region. Investigations on the QCSE in different low-dimensional systems, such as quantum wires [9] and dots [10], are being carried out in searching for systems with strong Stark effects.…”