Two-dimensional (2D) materials have drawn immense interests in scientific and technological communities, owing to their extraordinary properties and their tunability by gating, proximity, strain and external fields. For electronic applications, an ideal 2D material would have high mobility, air stability, sizable band gap, and be compatible with large scale synthesis. Here we demonstrate air stable field effect transistors using atomically thin few-layer PdSe2sheets that are sandwiched between hexagonal BN (hBN), with large saturation current > 350 μA/μm, and high field effect mobilities of ~ 700 and 10,000 cm2/Vs at 300 K and 2 K, respectively. At low temperatures, magnetotransport studies reveal unique octets in quantum oscillations that persist at all densities, arising from 2-fold spin and 4-fold valley degeneracies, which can be broken by in-plane and out-of-plane magnetic fields toward quantum Hall spin and orbital ferromagnetism.
The structure and properties of two‐dimensional phosphoborane sheets were computationally investigated using Density Functional Theory calculations. The calculated phonon spectrum and band structure point to dynamic stability and allowed characterization of the predicted two‐dimensional material as a direct‐gap semiconductor with a band gap of ~1.5 eV. The calculation of the optical properties showed that the two‐dimensional material has a relatively small absorptivity coefficient. The parameters of the mechanical properties characterize the two‐dimensional phosphoborane as a relatively soft material, similar to the monolayer of MoS2. Assessment of thermal stability by the method of molecular dynamics indicates sufficient stability of the predicted material, which makes it possible to observe it experimentally.
more » « less- Award ID(s):
- 1664379
- NSF-PAR ID:
- 10457475
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Journal of Computational Chemistry
- Volume:
- 41
- Issue:
- 15
- ISSN:
- 0192-8651
- Page Range / eLocation ID:
- p. 1456-1463
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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