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Title: Communication: Effect of accidental mode degeneracy on Raman intensity in 2D materials: Hybrid functional study of bilayer phosphorene

Authors:
;
Publication Date:
Sponsoring Org.:
USDOE
OSTI Identifier:
1261218
Grant/Contract Number:
AC02-05CH11231; SC0002623
Resource Type:
Journal Article: Publisher's Accepted Manuscript
Journal Name:
Journal of Chemical Physics
Additional Journal Information:
Journal Volume: 145; Journal Issue: 2; Related Information: CHORUS Timestamp: 2016-12-27 20:27:45; Journal ID: ISSN 0021-9606
Publisher:
American Institute of Physics
Country of Publication:
United States
Language:
English

Citation Formats

Sun, Yi-Yang, and Zhang, Shengbai. Communication: Effect of accidental mode degeneracy on Raman intensity in 2D materials: Hybrid functional study of bilayer phosphorene. United States: N. p., 2016. Web. doi:10.1063/1.4958460.
Sun, Yi-Yang, & Zhang, Shengbai. Communication: Effect of accidental mode degeneracy on Raman intensity in 2D materials: Hybrid functional study of bilayer phosphorene. United States. doi:10.1063/1.4958460.
Sun, Yi-Yang, and Zhang, Shengbai. 2016. "Communication: Effect of accidental mode degeneracy on Raman intensity in 2D materials: Hybrid functional study of bilayer phosphorene". United States. doi:10.1063/1.4958460.
@article{osti_1261218,
title = {Communication: Effect of accidental mode degeneracy on Raman intensity in 2D materials: Hybrid functional study of bilayer phosphorene},
author = {Sun, Yi-Yang and Zhang, Shengbai},
abstractNote = {},
doi = {10.1063/1.4958460},
journal = {Journal of Chemical Physics},
number = 2,
volume = 145,
place = {United States},
year = 2016,
month = 7
}

Journal Article:
Free Publicly Available Full Text
Publisher's Version of Record at 10.1063/1.4958460

Citation Metrics:
Cited by: 1work
Citation information provided by
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  • We investigate the effect of stacking order of bilayer black phosphorene on the device properties of p-MOSFET and n-MOSFET. Two layers of black phosphorus are stacked in three different orders and are used as channel material in both n-MOSFET and p-MOSFET devices. The effects of different stacking orders on electron and hole effective masses and output characteristics of MOSFETs, such as ON currents, ON/OFF ratio, and transconductance are analyzed. Our results show that about 1.37 times and 1.49 times increase in ON current is possible along armchair and zigzag directions, respectively, 55.11% variation in transconductance is possible along armchair direction,more » by changing stacking orders (AA, AB, and AC) and about 8 times increase in ON current is achievable by changing channel orientation (armchair or zigzag) in p-MOSFET. About 14.8 mV/V drain induced barrier lowering is observed for both p-MOSFET and n-MOSFET, which signifies good immunity to short channel effects.« less
  • In this work, device performances of tunneling field effect transistors (TFETs) based on phosphorene are explored via self-consistent atomistic quantum transport simulations. Phosphorene is an ultra-thin two-dimensional (2-D) material with a direct band gap suitable for TFETs applications. Our simulation shows that phosphorene TFETs exhibit subthreshold slope below 60 mV/dec and a wide range of on-current depending on the transport direction due to highly anisotropic band structures of phosphorene. By benchmarking with monolayer MoTe{sub 2} TFETs, we predict that phosphorene TFETs oriented in the small effective mass direction can yield much larger on-current at the same on-current/off-current ratio than monolayer MoTe{submore » 2} TFETs. It is also observed that a gate underlap structure is required for scaling down phosphorene TFETs in the small effective mass direction to suppress the source-to-drain direct tunneling leakage current.« less
  • We present a systematic comparison of the lattice structures, electronic density of states, and band gaps of actinide dioxides, AnO₂ (An=Th, Pa, U, Np, Pu, and Am) predicted by the Heyd-Scuseria-Ernzerhof screened hybrid density functional (HSE) with the self-consistent inclusion of spin-orbit coupling(SOC). The computed HSE lattice constants and band gaps of AnO₂ are in consistently good agreement with the available experimental data across the series, and differ little from earlier HSE results without SOC. ThO₂ is a simple band insulator (f⁰), while PaO₂, UO₂, and NpO₂ are predicted to be Mott insulators. The remainders (PuO₂ and AmO₂) show considerablemore » O2p/An5f mixing and are classified as charge-transfer insulators. We also compare our results for UO₂, NpO₂, and PuO₂with the PBE+U, self interaction correction (SIC), and dynamic mean-field theory (DMFT) many-body approximations.« less
  • Ballistic transport characteristics of metal-oxide semiconductor field effect transistors (MOSFETs) based on anisotropic two-dimensional materials monolayer HfS{sub 2} and phosphorene are explored through quantum transport simulations. We focus on the effects of the channel crystal orientation and the channel length scaling on device performances. Especially, the role of degenerate conduction band (CB) valleys in monolayer HfS{sub 2} is comprehensively analyzed. Benchmarking monolayer HfS{sub 2} with phosphorene MOSFETs, we predict that the effect of channel orientation on device performances is much weaker in monolayer HfS{sub 2} than in phosphorene due to the degenerate CB valleys of monolayer HfS{sub 2}. Our simulationsmore » also reveal that at 10 nm channel length scale, phosphorene MOSFETs outperform monolayer HfS{sub 2} MOSFETs in terms of the on-state current. However, it is observed that monolayer HfS{sub 2} MOSFETs may offer comparable, but a little bit degraded, device performances as compared with phosphorene MOSFETs at 5 nm channel length.« less
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