Shot Noise Induced by Electron-nuclear Spin-flip Scattering in a Nonequilibrium Quantum Wire

Abstract

We study the shot noise (nonequilibrium current fluctuation) associated with dynamic nuclear polarization in a nonequilibrium quantum wire (QW) fabricated in a two-dimensional electron gas. We observe that the spin-polarized conductance quantization of the QW in the integer quantum Hall regime collapses when the QW is voltage biased to be driven to nonequilibrium. By measuring the shot noise, we prove that the spin polarization of electrons in the QW is reduced to $\sim 0.7$ instead of unity as a result of electron-nuclear spin-flip scattering. The result is supported by Knight shift measurements of the QW using resistively detected NMR.

5 pages, 4 figures

References in corpus (7)

• Non-equilibrium Fluctuation Relations in a Quantum Coherent Conductor
• Evolution of the Kondo Effect in a Quantum Dot Probed by the Shot Noise
• Fast nuclear spin hyperpolarization of phosphorus in silicon
• NMR Evidence for Spin Canting in a Bilayer nu = 2 Quantum Hall System
• Conductance Anomaly and Fano Factor Reduction in Quantum Point Contacts
• Nuclear spin coherence in a quantum wire
• Knight shift detection using gate-induced decoupling of the hyperfine interaction in quantum Hall edge channels

Cited by in corpus (7)

• Shot Noise in Mesoscopic Systems: from Single Particles to Quantum Liquids
• Resistively-detected NMR lineshapes in a quasi-one dimensional electron system
• Observation of finite excess noise in the voltage-biased quantum Hall regime as a precursor for breakdown
• Voltage induced conversion of helical to uniform nuclear spin polarization in a quantum wire
• Probing strain modulation in a gate-defined one dimensional electron system
• Dynamic nuclear polarization at high Landau levels in a quantum point contact
• Two-step breakdown of a local v = 1 quantum Hall state