Work

Spin properties in droplet epitaxy grown telecom quantum dots

Year: 2025

Type: article

Abstract: We investigate the spin properties of InAs/InGaAs/InP quantum dots grown by metalorganic vapor-phase epitaxy (MOVPE) deposition using droplet epitaxy, which emits in the telecom C band. Using pump-probe Faraday ellipticity measurements, we determine electron and hole g factors of | g e | = 0.93 and | g h | = 0.47 , with the electron g factor being nearly twice as low as typical molecular beam epitaxy Stranski-Krastanov (SK) grown samples. Most significantly, we measure a longitudinal spin relaxation time T 1 = 3.0 µ s , representing an order of magnitude improvement over comparable MBE SK grown samples. Despite significant electron g -factor anisotropy, we observed that it is reduced relative to similar material composition samples grown with MBE or MOVPE SK methods. We attribute this g -factor anisotropy and spin lifetime improvements to the enhanced structural symmetry achieved via MOVPE droplet epitaxy, which mitigates the inherent structural asymmetry in strain-driven growth approaches for InAs/InP quantum dots. These results demonstrate that MOVPE droplet epitaxy-grown InAs/InGaAs/InP quantum dots exhibit favorable spin properties for potential implementation in quantum information applications.

Source: Physical review. B./Physical review. B

DOI: 10.1103/bm22-smcp

Authors: Marius Cizauskas, Elisa M. Sala, Jon Heffernan, A. Mark Fox, Manfred Bayer, Alex Greilich

Institutions: TU Dortmund University, University of Sheffield

Language: English

Topic: Semiconductor Quantum Structures and Devices

Subfield: Atomic and Molecular Physics, and Optics

Field: Physics and Astronomy

Domain: Physical Sciences

Open Access status: hybrid

Funders: Bundesministerium für Bildung und Forschung, Engineering and Physical Sciences Research Council

Awards: Light-matter interactions and quantum photonics in nano-scale semiconductor structures and devices, Verbundprojekt: Quantenrepeater.Net - QR.N -, G5739533682