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NiO is a promising alternative to p-GaN as a hole injection layer for normally-off lateral transistors or low on-resistance vertical heterojunction rectifiers. The valence band offsets of sputtered NiO on c-plane, vertical geometry homoepitaxial GaN structures were measured by x-ray photoelectron spectroscopy as a function of annealing temperatures to 600 °C. This allowed determination of the band alignment from the measured bandgap of NiO. This alignment was type II, staggered gap for both as-deposited and annealed samples. For as-deposited heterojunction, ΔEV = 2.89 eV and ΔEC = −2.39 eV, while for all the annealed samples, ΔEVvalues were in the range of 3.2–3.4 eV and ΔECvalues were in the range of −(2.87–3.05) eV. The bandgap of NiO was reduced from 3.90 eV as-deposited to 3.72 eV after 600 °C annealing, which accounts for much of the absolute change in ΔEV − ΔEC. At least some of the spread in reported band offsets for the NiO/GaN system may arise from differences in their thermal history.
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Noise induced order for skew-products over a non-uniformly expanding base
Abstract Noise-induced order (NIO) is the phenomenon by which the chaotic regime of a deterministic system is destroyed in the presence of noise. In this manuscript, we establish NIO for a natural class of systems of dimension ⩾ 2 consisting of a fiber-contracting skew product a over nonuniformly-expanding one-dimensional system.
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- Award ID(s):
- 2009431
- PAR ID:
- 10415579
- Date Published:
- Journal Name:
- Nonlinearity
- Volume:
- 35
- Issue:
- 10
- ISSN:
- 0951-7715
- Page Range / eLocation ID:
- 5481 to 5504
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1088/1361-6544/ac87e8
