InGaAs/InAlAs Five-Layer Asymmetric Coupled Quantum Well and Its Application to Compact and Low-Voltage Optical Switch

An InGaAs/InAlAs five-layer asymmetric coupled quantum well (FACQW) for giant electrorefractive (ER) sensitivity was proposed and studied theoretically and experimentally. Giant ER sensitivity |
dn/dF
| (4.4 × 10
^-4
cm/kV) over 100 nm wavelength range can be expected at around electric field
F =-30~ -60
kV/cm. In addition, a compact and low-voltage FACQW modulator and a 2 × 2 switch with multi-mode interferer (MMI) couplers were also proposed and static operation characteristics were analyzed using BPM. The switching voltage can be reduced to 0.1~0.2V.