Exfoliated hexagonal BN as gate dielectric for InSb nanowire quantum dots with improved gate hysteresis and charge noise
| Autor: | Sasa Gazibegovic, Erik P. A. M. Bakkers, Benjamin Pestka, Kilian Flöhr, Jürgen Schubert, Markus Morgenstern, Marcus Liebmann, Diana Car, Thomas Schäpers, Sebastian Heedt, Felix Jekat |
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| Rok vydání: | 2020 |
| Předmět: |
010302 applied physics
Materials science Physics and Astronomy (miscellaneous) Condensed matter physics Condensed Matter - Mesoscale and Nanoscale Physics Gate dielectric Nanowire FOS: Physical sciences 02 engineering and technology Dielectric 021001 nanoscience & nanotechnology Condensed Matter::Mesoscopic Systems and Quantum Hall Effect 01 natural sciences Noise (electronics) Hysteresis Condensed Matter::Materials Science Quantum dot 0103 physical sciences Mesoscale and Nanoscale Physics (cond-mat.mes-hall) Coulomb 0210 nano-technology Excitation |
| Zdroj: | Applied Physics Letters |
| ISSN: | 0003-6951 |
| DOI: | 10.1063/5.0002112 |
| Popis: | We characterize InSb quantum dots induced by bottom finger gates within a nanowire that is grown via the vapor-liquid-solid process. The gates are separated from the nanowire by an exfoliated 35\,nm thin hexagonal BN flake. We probe the Coulomb diamonds of the gate induced quantum dot exhibiting charging energies of $\sim 2.5\,\mathrm{meV}$ and orbital excitation energies up to $0.3\,\mathrm{meV}$. The gate hysteresis for sweeps covering 5 Coulomb diamonds reveals an energy hysteresis of only $60\mathrm{\mu eV}$ between upwards and downwards sweeps. Charge noise is studied via long-term measurements at the slope of a Coulomb peak revealing potential fluctuations of $\sim 1\,\mu \mathrm{eV}/\mathrm{\sqrt{Hz}}$ at 1\,Hz. This makes h-BN the dielectric with the currently lowest gate hysteresis and lowest low-frequency potential fluctuations reported for low-gap III-V nanowires. The extracted values are similar to state-of-the art quantum dots within Si/SiGe and Si/SiO${_2}$ systems. |
| Databáze: | OpenAIRE |
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