Regensburg 2025 – scientific programme

Parts | Days | Selection | Search | Updates | Downloads | Help

HL: Fachverband Halbleiterphysik

HL 29: Poster II

HL 29.58: Poster

Tuesday, March 18, 2025, 18:00–20:00, P1

Shutter synchronized deposition in molecular epitaxy for wafer scale homogeneous quantum emitter growth — •Elias Kersting, Hans Georg Babin, Nikolai Spitzer, Andreas Wieck, and Arne Ludwig — Lehrstuhl für Angewandte Festkörperphysik, Ruhr-Universität Bochum, Deutschland

Most quantum dot (QD) based single photon emitters today are based on random position nucleated QDs with spectrally broad emission properties. Deterministic QD growth in position and emitter wavelength would be highly appreciated for large-scale and good turnabout chip manufacturing. Local droplet etching during molecular beam epitaxy is an all-in-situ method to predetermine the nucleation site of quantum dots. As recently demonstrated, this method can produce strain-free GaAs QDs with excellent photonic and spin properties. We use random position droplet nucleation and hole filling demonstrating enhanced emitter wavelength homogeneity on a wafer scale. By shutter synchronized rotation and ideal growth parameters, we grow QDs with a peak emission wavelength spread of no more than 2 nm on a full 2" diameter area with a narrow inhomogeneous ensemble broadening. While the emission wavelength of these QDs is < 800 nm, we can use this random local droplet nucleation, nanohole drilling and InAs infilling to produce QDs emitting in the telecom optical fibre transparency window around 1.3 µm, the so-called O-band. For this approach, we demonstrate 2" wafer scale control of the emission wavelength and excellent uniformity. We discuss our methodology, structural and optical properties.

Keywords: Molecular beam epitaxy (MBE); Local droplet etching (LDE); Quantum Dots