Abstract
A study of the resistively detected nuclear magnetic resonance (RDNMR) lineshape in the vicinity of ν = 1 was performed on a high-mobility 2D electron gas formed in GaAs/AlGaAs. In higher Landau levels, application of an RF field at the nuclear magnetic resonance frequency coincides with an observed minimum in the longitudinal resistance, as predicted by the simple hyperfine interaction picture. Near ν = 1 however, an anomalous dispersive lineshape is observed where a resistance peak follows the usual minimum. In an effort to understand the origin of this anomalous peak we have studied the resonance under various RF and sample conditions. Interestingly, we show that the lineshape can be completely inverted by simply applying a DC current. We interpret this as evidence that the minima and maxima in the lineshape originate from two distinct mechanisms.
Original language | English (US) |
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Pages (from-to) | 990-994 |
Number of pages | 5 |
Journal | Physica E: Low-Dimensional Systems and Nanostructures |
Volume | 40 |
Issue number | 5 |
DOIs | |
State | Published - Mar 2008 |
Externally published | Yes |
All Science Journal Classification (ASJC) codes
- Electronic, Optical and Magnetic Materials
- Atomic and Molecular Physics, and Optics
- Condensed Matter Physics
Keywords
- Dispersive lineshape
- Hyperfine interaction
- Nuclear magnetic resonance
- Quantum Hall effect