Skip to main content

Confocal microscopy for T centres in silicon

Resource type
Thesis type
(Thesis) M.Sc.
Date created
Spin defects in silicon boast long lifetimes and potential scalability with existing nanofabrication foundry processes. Paired with silicon photonics, optically active spin defects offer a path to scalable optically interfaced quantum technologies, such as quantum communication networks and optically coupled qubits. The T centre in silicon is a paramagnetic radiation damage centre that is optically active in the telecommunication O-band, making it a strong candidate for spin-photon interfaces. Certain single-photon based quantum technologies rely on the production of indistinguishable photons, a characteristic which may be found from an optical centre’s zero-phonon line. In this study we measure the zero-phonon line fraction of the T centre in silicon-28 at 4.2 K to be 22.9 ± 0.2%. Isolating optical defects in silicon is difficult due to the relatively low radiative efficiencies of silicon-based emitters and silicon’s large refractive index (n ≈ 3.5), trapping light by total internal reflection. Estimates using bound exciton ground state lifetime measurements from previous studies suggest isolation and measurement of single T centres is possible by confocal microscopy. We develop a confocal microscope system designed for measuring photoluminescence from cryogenically cooled silicon and characterize its resolution performance in reflection and above-band photoluminescence. Silicon photonic ‘micropuck’ structures were designed and fabricated to increase collection efficiency from single T centres into a microscope objective.
Copyright statement
Copyright is held by the author.
This thesis may be printed or downloaded for non-commercial research and scholarly purposes.
Scholarly level
Supervisor or Senior Supervisor
Thesis advisor: Simmons, Stephanie
Member of collection
Download file Size
etd20834.pdf 9.49 MB

Views & downloads - as of June 2023

Views: 124
Downloads: 5