Lateral Ordering, Position, and Number Control of Self-Organized Quantum Dots: The Key to Future Functional Nanophotonic Devices

Lateral ordering, position, and number control of self-organized epitaxial semiconductor quantum dots (QDs) are demonstrated. Straight linear InAs QD arrays are formed by self-organized anisotropic strain engineering of an InGaAsP/InP (1 0 0) superlattice template in chemical beam epitaxy. The QD emission wavelength at room temperature is tuned into the important 1.55 mu m telecom wavelength region through the insertion of ultrathin GaAs interlayers. Guided self-organized anisotropic strain engineering is demonstrated on shallow- and deep-patterned GaAs (3 1 1)B substrates by molecular beam epitaxy for the formation of complex InGaAs QD arrays. Lateral positioning and number control of InAs QDs, down to a single QD, are demonstrated on truncated InP (1 0 0) pyramids by selective-area metal-organic vapor phase epitaxy. Sharp emission around 1.55 mu m is observed Well above liquid nitrogen temperatures. The regrowth of a passive waveguide structure establishes submicrometer-scale active-passive integration. The demonstrated control over QD formation is the key to future functional nanophotonic devices and paves the way toward the ultimates of photonic-integrated circuits operating at the single and multiple electron and photon level with control of the quantum mechanical and electromagnetic interactions.