Enhanced electro-optic effect in GaInAsP–InP three-step quantum wells

Abstract

We report on the enhanced electro-optic coefficient of GaInAsP three-step quantum wells ͑3SQW͒ for high power electrorefraction modulator applications. Measured electro-optic coefficient of the 3SQW is nearly three times higher than the conventional rectangular quantum well ͑RQW͒ at ϭ1.55 m. The enhanced electro-optic effect, combined with a low optical absorption coefficient ␣Ͻ1 cm Ϫ1 in the 3SQW increases a modulator figure of merit by nearly 36 times, and decreases the power consumption by nearly one order of magnitude compared with a conventional RQW design.

Highly linear and efficient phase modulators based on GaInAsP-InP three-step quantum wells

“…Our earlier experiments indicate that three-step quantum wells ͑3SQWs͒ have nearly three times larger electro-optic effect compared to conventional rectangular quantum wells ͑RQWs͒. 5 A marked difference between stepped and rectangular quantum wells is the asymmetry of the stepped quantum wells that leads to spatial separation of electron and hole wave functions, resulting in an induced internal electric field. 6 Similar to the earlier report on strained AlGaN/GaN quantum wells, 7 we show that the internal electric field for a properly designed 3SQW can enhance the linear electro-optic ͑LEO͒ effect.…”

“…This shows about 2.6 times higher linear electro-optic coefficient for the 3SQW compared with the RQW, which is close to the measured enhancement value of 2.8 reported earlier. 5 Although enhancement of the linear electro-optic effect in the 3SQW is significant, the quadratic component is nearly unchanged, and hence a perfect linearization is not possible. We used the nonlinear relation between the electric field and the applied voltage to a p-i-n structure in order to compensate for the nonlinear relation between the change of index and the electric field.…”

Hybrid optoelectronic correlator architecture for shift-invariant target recognition

“…The LPF can be implemented with 0.1 nf capacitance and 10 ohm resistance would have a response time of 1ns. Finally, the SLM could be realized with an array of high speed stepped quantum wells [16][17][18][19][20]. An SLM based on these elements has a response time of ~16 ns, which is orders of magnitude faster than the conventional SLM discussed in section 2.…”

Pockels effect and effective phase modulation in Mach–Zehnder modulators constructed by gain quantum well nanostructures

“…There have been extensive efforts to enhance the electro-optic effects and improve the electro-optic modulators for transverse electric (TE) waves with simultaneously high electro-optic coefficients and a low optical absorption loss in semiconductor quantum wells (QWs) from interband transitions by either optimizing the confinement potential or integrating a compressively strained quantum well (QW) amplifier to compensate optical absorption loss in QW modulators [10][11][12][13]. For example, Mohseni et al [12] studied efficient phase modulators based on GaInAsP-InP three-step quantum wells, and measured the modulation efficiency is 48 /V mm°.…”