Phys.org November 8, 2023
The use of single electron spins in quantum dots as qubits requires detailed knowledge about the processes involved in their initialization and operation as well as their relaxation and decoherence. In optical schemes for such spin qubits, spin-flip Raman as well as Auger processes play an important role, in addition to environment-induced spin relaxation. An international team of researchers (Germany, USA – UCLA) demonstrated how to quantitatively access all the spin-related processes in one go by monitoring the charge fluctuations of the quantum dot. They used resonance fluorescence and analyzed the charge fluctuations in terms of waiting-time distributions and full counting statistics characterized by factorial cumulants. According to the researchers their technique makes it possible to re-evaluate even older, seemingly useless data and to discover signals that had previously remained hidden… read more. Open Access TECHNICAL ARTICLE
Relevant states and transitions for the quantum-dot system. (a) Full system and (b) effective three-state system. Credit: Phys. Rev. Research 5, 043103, 1 November 2023Â