Resistively detected NMR in a triple-gate quantum point contact: Magnetic field dependence
| Autor: | K. Nagase, Annisa Noorhidayati, Shunta Maeda, Muhammad Fauzi Sahdan, Yoshiro Hirayama, M. H. Fauzi, Ken Sato |
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| Rok vydání: | 2020 |
| Předmět: |
Physics
Condensed matter physics Quantum point contact Field strength 02 engineering and technology Landau quantization Electron Quantum Hall effect 021001 nanoscience & nanotechnology 01 natural sciences Magnetic field Dipole 0103 physical sciences Quadrupole 010306 general physics 0210 nano-technology |
| Zdroj: | Physical Review B. 101 |
| ISSN: | 2469-9969 2469-9950 |
| Popis: | We report a resistively detected nuclear magnetic resonance (RDNMR) measurement in a GaAs-based quantum point contact in the quantum Hall breakdown regime. We focus on the detection of the $^{75}\mathrm{As}$ RDNMR signal at different perpendicular magnetic fields in the presence of electrons occupying the lowest Landau level. We confirm successful RDNMR detection down to $B=1.25\phantom{\rule{0.16em}{0ex}}\mathrm{T}$ ($B=3.5\phantom{\rule{0.16em}{0ex}}\mathrm{T}$) using a high-mobility (low-mobility) device. All the RDNMR signals exhibit a threefold spectra attributed to electric quadrupole interaction. We find that the separation between the central transition and its satellite, ${\mathrm{\ensuremath{\Delta}}}_{f}\ensuremath{\approx}20\phantom{\rule{0.16em}{0ex}}\mathrm{kHz}$, remains unaffected by magnetic-field variation. Interestingly, the central NMR linewidths vary with the field strength. Above $B=3\phantom{\rule{0.16em}{0ex}}\mathrm{T}$, the linewidth tends to saturate around 13 kHz. Below $B=3\phantom{\rule{0.16em}{0ex}}\mathrm{T}$, the linewidth decreases in proportion with field and approaches a lower limit of 1 kHz corresponding to the GaAs nuclear dipole interaction as the field decreases to $B=1.25\phantom{\rule{0.16em}{0ex}}\mathrm{T}$. |
| Databáze: | OpenAIRE |
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