Writing Spin in a Quantum Dot with Ferromagnetic and Superconducting Electrodes

Abstract

We propose an efficient mechanism for the operation of writing spin in a quantum dot, which is an ideal candidate for qubit. The idea is based on the Andreev reflection induced spin polarization (ARISP) in a ferromagnetic / quantum-dot / superconductor system. We find that on the resonance of Andreev reflection, the spin polarization of quantum dot strongly denpends on the magnetization of ferromagnetic electrode, and the sign of the spin polarization is controllable by bias voltage. In the presence of intradot Coulomb interaction, we show that ARISP effect can still survive as long as the charging energy is comparable to the superconducting gap. Detailed conditions and properties of ARISP are also discussed.

10 pages, 3 figures

References in corpus (7)

• Spin relaxation in semiconductor quantum dots
• Spin-flip transitions between Zeeman sublevels in semiconductor quantum dots
• Quantum Dot as Spin Filter and Spin Memory
• A Quantum Dot in the Kondo Regime Coupled to Superconductors
• Resonant Andreev Tunneling in Strongly Interacting Quantum Dots
• Excess Kondo resonance in a quantum dot device with normal and superconducting leads: the physics of Andreev-normal co-tunneling
• Correlated two-electron transport: a principle for a novel charge pump

Cited by in corpus (6)

• Bias-controllable intrinsic spin polarization in a quantum dot
• Spin-dependent Andreev reflection tunneling through a quantum dot with intradot spin-flip scattering
• Adiabatic pumping in a double-dot Cooper-pair beam splitter
• Interplay between direct and crossed Andreev reflections in hybrid nano-structures
• Quantum transport through a double Aharonov-Bohm-interferometer in the presence of Andreev reflection
• Well-defined Fano effect in the Andreev reflection process of a parallel double-quantum-dot structure