Spontaneous Transition to a Correlated Phase of Skyrmions Observed in Real Space

Abstract

We conduct photoluminescence microscopy that is sensitive to both electron and nuclear spin polarization to investigate the changes that occur in the magnetic ordering in the vicinity of the first integer quantum Hall state in a GaAs 2D electron system (2DES). We observe a discontinuity in the electron spin polarization and nuclear spin longitudinal relaxation time which heralds a spontaneous transition to a phase of magnetic skyrmions. We image in real space the spin phase domains that coexist at this transition, and observe hysteresis in their formation as a function of the 2DES's chemical potential. Based on measurements in a tilted magnetic field orientation, we found that the transition is protected by an energy gap containing the Zeeman energy, and conclude that the skyrmions here have formed as an ensemble.

arXiv comment4 figures

References in corpus (22)

• Evidence for Skyrmions and Single Spin Flips in the Integer Quantized Hall Effect
• Evidence of Skyrmion excitations about $\nu =1$ in n-Modulation Doped Single Quantum Wells by Inter-band Optical Transmission
• Unraveling the spin polarization of the v = 5/2 fractional quantum Hall state
• Electrically-Controlled Nuclear Spin Polarization and Relaxation by Quantum-Hall states
• Nuclear Spins in Nanostructures
• Universal behavior of the electron g-factor in GaAs/AlGaAs quantum wells
• Collective Excitations, NMR, and Phase Transitions in Skyrme Crystals
• Charged Excitons in a Dilute 2D Electron Gas in a High Magnetic Field
• Giant Low Temperature Heat Capacity of GaAs Quantum Wells near Landau Level Filling $\nu$=1
• Long-lived charged multiple-exciton complexes in strong magnetic fields
• Charged exctions in the fractional quantum Hall regime
• Soft Spin Wave Near nu=1: Evidence for a Magnetic Instability in Skyrmion Systems
• Imaging the Conductance of Integer and Fractional Quantum Hall Edge States
• Optical absorption to probe the quantum Hall ferromagnet at filling factor $\nu =1$
• Skymrion lattice melting in the quantum Hall system
• Spectroscopic Evidence for the Localization of Skyrmions near Nu=1 as T->0
• The absorption spectrum around nu=1: evidence for a small size Skyrmion
• Quasiexcitons in Incompressible Quantum Liquids
• Non-equilibrium fractional quantum Hall states visualized by optically detected MRI
• Disorder-induced stabilization of the quantum Hall ferromagnet
• Hyperfine-controlled domain-wall motion observed in real space and time
• Disorder Enhanced Nuclear Spin Relaxation at Landau Level Filling Factor One