"Quantum dots (QDs) are often considered as promising candidates for applications in a variety of novel devices with spin-enabling functionality, e.g. in spin light-emitting devices, for spin filtering, as well as in quantum information technology," the authors write.
The researchers showed that independent (free) carriers are more efficient than electron-hole pairs (excitons) for creating specific spin orientations in InAs quantum dots.
Nanotechweb.org is running a very nice description of this work, which is a collaboration between Linköping University, Sweden and UC San Diego's Jacobs School of Engineering.
According to the nanotechweb.org story,
This finding is relevant for future quantum communication and quantum information storage because it points out that separate carrier injection can be advantageous for next-generation spintronic devices based on QD spins.
The paper, "Spin injection in lateral InAs quantum dot structures by optical orientation spectroscopy," appeared in print in the journal Nanotechnology. Researchers at Linköping University performed the characterization work. Suwaree Suraprapapich performed the sample growth when she was a visiting electrical engineering Ph.D. student in the group of electrical engineering professor Charles W Tu at UC San Diego's Jacobs School of Engineering. Professor Tu also serves as Associate Dean of the Jacobs School of Engineering.
"Suwaree grew indium arsenide (InAs) single-quantum-dot, double-quantum-dot, and quantum-ring samples by gas-source molecular beam epitaxy in my lab during her time at the Jacobs School," said Tu.