ANALYSIS OF SWITCHING DYNAMICS OF ASYMMETRIC FABRY-PEROT SYMMETRICAL SELF-ELECTRO-OPTIC EFFECT DEVICES WITH EXTREMELY SHALLOW QUANTUM-WELLS

This article investigates the effects of asymmetric Fabry-Perot (AFP) cavity structures on the switching dynamics of symmetric self-electro- optic effect devices (S-SEEDs) made of Al(x)G(1-x)As/GaAs (x less than or equal to 0.05) extremely shallow quantum wells (ESQWs). We analyze the switching dynamics of AFP ESQW S-SEEDs (AE-SEEDs) by means of an impulse photocurrent response function and corresponding voltage trans ients of the two AFP p-i(ESQWs)-n diodes connected in series. The phot ocurrent response function is obtained by using an appropriate electro n-hole pair generation rate and the Green's function method. The respo nse function includes the LO phonon scattering from bound to continuum states and the carrier transit in the continuum states, Large interna l optical fields and thin intrinsic region thicknesses of AFP SEEDs re duce the required incident switching energy and operating voltage, res pectively. Our analyses show that the switching energy of an impedance -matched AL-SEED is about 3.0 fJ/mu m(2), while that of a conventional antireflection coated ESQW S-SEED (E-SEED) is about 4.1 fJ/mu m(2). C onsidering practical RC time constants and device sizes, the switching time of an impedance-matched AE-SEED is found to be as low as 10 ps w hile that of an E-SEED is about 18 ps for the same incident energy of 4.1 fJ/mu m(2). (C) 1997 American Institute of Physics.