Nuclear Polarization in Quantum Point Contacts in an In-Plane Magnetic Field

Abstract

Nuclear spin polarization is typically generated in GaAs quantum point contacts (QPCs) when an out-of-plane magnetic field gives rise to spin-polarized quantum Hall edge states, and a voltage bias drives transitions between the edge states via electron-nuclear flip-flop scattering. Here, we report a similar effect for QPCs in an in-plane magnetic field, where currents are spin polarized but edge states are not formed. The nuclear polarization gives rise to hysteresis in the d.c. transport characteristics, with relaxation timescales around 100 seconds. The dependence of anomalous QPC conductance features on nuclear polarization provides a useful test of their spin-sensitivity.

5 pages

References in corpus (6)

• Magnetic impurity formation in quantum point contacts
• Dynamic Nuclear Polarization with Single Electron Spins
• Large nuclear Overhauser fields detected in vertically-coupled double quantum dots
• Non-Kondo zero-bias anomaly in quantum wires
• Nuclear spin coherence in a quantum wire
• Theory of NMR in semiconductor quantum point contact devices

Cited by in corpus (8)

• Helical nuclear spin order in a strip of stripes in the Quantum Hall regime
• Electronic magnetization of a quantum point contact measured by nuclear magnetic resonance
• Dynamic Nuclear Polarization in the Fractional Quantum Hall Regime
• Landauer-Büttiker approach for hyperfine mediated electronic transport in the integer quantum Hall regime
• Resistive detection of nuclear spins in a single quantum dot under Kondo effect regime
• Detection of spin injection into a double quantum dot: Violation of magnetic-field-inversion symmetry of nuclear polarization instabilities
• Dipole-like dynamical nuclear spin polarization around a quantum point contact
• Anisotropic nuclear-spin diffusion in double quantum wells