We present a novel growth technique for fabricating low-density InAs/GaAs quantum dots that emit in the telecom O-band. This method combines local droplet etching on GaAs surfaces using gallium with Stranski–Krastanov growth initiated by InAs deposition. Quantum dots nucleate directly within nanoholes, avoiding the critical layer thickness typical of standard InAs Stranski–Krastanov growth, resulting in larger, low-density quantum dots. InGaAs strain reduction layers further redshift the emission into and beyond the telecom O-band. Photoluminescence spectra show a small energy difference between ground and excited states, while capacitance-voltage spectroscopy reveal small Coulomb blockade energy. Atomic force microscopy analysis indicates that quantum dots formed within nanoholes exhibit a larger volume compared to standard quantum dots. Additionally, these nanohole nucleated quantum dots require less indium to achieve O-band emission and demonstrate comparable or even better homogeneity, as indicated by the full-width at half-maximum. This improved homogeneity, low density, and increased size make these quantum dots particularly suitable for single-photon sources in quantum communication applications.
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