Physics – Quantum Physics
Scientific paper
2006-10-13
Physics
Quantum Physics
Scientific paper
Ability to read-out the state of a single confined spin lies at the heart of solid-state quantum information processing. While all-optical spin measurements using Faraday rotation has been successfully implemented in ensembles of semiconductor spins, read-out of a single semiconductor spin has only been achieved using transport measurements based on spin-charge conversion. Here, we demonstrate an all-optical dispersive measurement of the spin-state of a single electron trapped in a semiconductor quantum dot. We obtain information on the spin state through conditional Faraday rotation of a spectrally detuned optical field, induced by the polarization- and spin-selective trion (charged quantum dot) transitions. To assess the sensitivity of the technique, we use an independent resonant laser for spin-state preparation. An all-optical dispersive measurement on single spins has the important advantage of channeling the measurement back-action onto a conjugate observable, thereby allowing for repetitive or continuous quantum nondemolition (QND) read-out of the spin-state. We infer from our results that there are of order unity back-action induced spin-flip Raman scattering events within our measurement timescale. Therefore, straightforward improvements such as the use of a solid-immersion lens and higher efficiency detectors would allow for back-action evading spin measurements, without the need for a cavity.
Atature Mete
Badolato Antonio
Dreiser Jan
Imamoglu Atac
No associations
LandOfFree
Observation of Faraday rotation from a single confined spin does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Observation of Faraday rotation from a single confined spin, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Observation of Faraday rotation from a single confined spin will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-665363