Abstract
Repeated injection of spin-polarized carriers in a quantum dot (QD) leads to the polarization of nuclear spins, a process known as dynamic nuclear spin polarization (DNP). Here, we report the observation of p-shell carrier assisted DNP in single QDs at zero external magnetic field. The nuclear field - measured by using the Overhauser shift of the singly charged exciton state of the QDs - continues to increase, even after the carrier population in the s-shell saturates. This is also accompanied by an abrupt increase in nuclear spin buildup time as p-shell emission overtakes that of the s shell. We attribute the observation to p-shell electrons strongly altering the nuclear spin dynamics in the QD, supported by numerical simulation results based on a rate equation model of coupling between electron and nuclear spin system. Dynamic nuclear spin polarization with p-shell carriers could open up avenues for further control to increase the degree of nuclear spin polarization in QDs.
Original language | English |
---|---|
Article number | 125306 |
Number of pages | 7 |
Journal | Physical Review B |
Volume | 93 |
Issue number | 12 |
DOIs | |
Publication status | Published - 16 Mar 2016 |
Research Groups and Themes
- QETLabs
- Photonics and Quantum
Keywords
- quantum dot
- spintronics
- nuclear spin
Fingerprint
Dive into the research topics of 'p-shell carrier assisted dynamic nuclear spin polarization in single quantum dots at zero external magnetic field'. Together they form a unique fingerprint.Profiles
-
Dr Edmund G H Harbord
- School of Electrical, Electronic and Mechanical Engineering - Senior Lecturer in Quantum Communication Technologies
- QET Labs
Person: Academic , Member