We theoretically examine a small current through double quantum dots with Pauli spin blockade, in which electrons cannot be transported without spin-flip or higher-order tunnel processes (cotunneling). Analytical expressions for the current are given in both cases of sequential tunneling and resonant tunneling between the quantum dots and leads. In the former case, the cotunneling weakens the spin blockade and increases a coherent component of the current. When the cotunneling can be disregarded, effective magnetic fields created by nuclear spins (Overhauser fields) can be detected by the observation of the current. In the case of resonant tunneling with Zeeman splitting in an external magnetic field (∼ 1 T), small Overhauser fields (∼ 5 mT) could be detected by the fine tuning of the resonant condition.
|ジャーナル||Physica E: Low-Dimensional Systems and Nanostructures|
|出版ステータス||Published - 2008 3 1|
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Atomic and Molecular Physics, and Optics
- Condensed Matter Physics