The electron transport that occurs within wurtzite zinc oxide and the application of stress

ABSTRACTWe examine how stress has the potential to shape the character of the electron transport that occurs within ZnO. In order to narrow the scope of this analysis, we focus on a determination of the velocity-field characteristics associated with bulk wurtzite ZnO. Monte Carlo simulations of the electron transport are pursued for the purposes of this analysis. Rather than focusing on the impact of stress in of itself, instead we focus on the changes that occur to the energy gap through the application of stress, i.e., energy gap variations provide a proxy for the amount of stress. Our results demonstrate that stress plays a significant role in shaping the form of the velocity-field characteristics associated with ZnO. This dependence could potentially be exploited for device application purposes.

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Steady-state and transient electron transport within bulk wurtzite zinc oxide and the resultant electron device performance

MRS Proceedings ◽

10.1557/opl.2013.535 ◽

2013 ◽

Vol 1577 ◽

Cited By ~ 3

Author(s):

Walid A. Hadi ◽

Michael S. Shur ◽

Stephen K. O’Leary

Keyword(s):

Monte Carlo ◽

Zinc Oxide ◽

Steady State ◽

Electron Transport ◽

Monte Carlo Simulations ◽

Indium Nitride ◽

Device Performance ◽

Electron Drift ◽

Electron Device ◽

Velocity Enhancement

ABSTRACTWe review some recent results related to the steady-state and transient electron transport that occurs within bulk wurtzite zinc oxide. We employ three-valley Monte Carlo simulations of the electron transport within this material for the purposes of this analysis. Using these results, we devise a means of rendering transparent the electron drift velocity enhancement offered by transient electron transport over steady-state electron transport. A comparison, with results corresponding to gallium nitride, indium nitride, and aluminum nitride, is provided. The device implications of these results are then presented.

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The effect of ionic defect interactions on the hydration of yttrium-doped barium zirconate

Physical Chemistry Chemical Physics ◽

10.1039/d0cp06587k ◽

2021 ◽

Author(s):

Sebastian Eisele ◽

Fabian M. Draber ◽

Steffen Grieshammer

Keyword(s):

Monte Carlo ◽

Monte Carlo Simulations ◽

First Principles ◽

Barium Zirconate ◽

First Principles Calculations ◽

Defect Interactions ◽

The Impact ◽

Ionic Defect

First principles calculations and Monte Carlo simulations reveal the impact of defect interactions on the hydration of barium-zirconate.

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A Monte Carlo Determination of Dose and Range Uncertainties for Preclinical Studies with a Proton Beam

Cancers ◽

10.3390/cancers13081889 ◽

2021 ◽

Vol 13 (8) ◽

pp. 1889

Author(s):

Arthur Bongrand ◽

Charbel Koumeir ◽

Daphnée Villoing ◽

Arnaud Guertin ◽

Ferid Haddad ◽

...

Keyword(s):

Monte Carlo ◽

Monte Carlo Simulations ◽

Proton Beam ◽

Dose Response ◽

Small Animal ◽

Absorbed Dose ◽

Normal Tissue Damage ◽

Dose Homogeneity ◽

And Control ◽

The Impact

Proton therapy (PRT) is an irradiation technique that aims at limiting normal tissue damage while maintaining the tumor response. To study its specificities, the ARRONAX cyclotron is currently developing a preclinical structure compatible with biological experiments. A prerequisite is to identify and control uncertainties on the ARRONAX beamline, which can lead to significant biases in the observed biological results and dose–response relationships, as for any facility. This paper summarizes and quantifies the impact of uncertainty on proton range, absorbed dose, and dose homogeneity in a preclinical context of cell or small animal irradiation on the Bragg curve, using Monte Carlo simulations. All possible sources of uncertainty were investigated and discussed independently. Those with a significant impact were identified, and protocols were established to reduce their consequences. Overall, the uncertainties evaluated were similar to those from clinical practice and are considered compatible with the performance of radiobiological experiments, as well as the study of dose–response relationships on this proton beam. Another conclusion of this study is that Monte Carlo simulations can be used to help build preclinical lines in other setups.

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Monte Carlo simulations of electron transport in 4H-SiC using the DFT-calculated density of states

Journal of Computational Electronics ◽

10.1007/s10825-021-01658-y ◽

2021 ◽

Author(s):

Janusz Wozny ◽

Andrii Kovalchuk ◽

Zbigniew Lisik ◽

Jacek Podgorski ◽

Piotr Bugalski ◽

...

Keyword(s):

Silicon Carbide ◽

Monte Carlo ◽

Electron Transport ◽

Monte Carlo Simulations ◽

Electric Fields ◽

Density Of States ◽

Electron Mobility ◽

Crucial Issue ◽

Calculated Density ◽

Correct Calculation

AbstractWe carry out Monte Carlo simulations of electron transport in 4H-silicon carbide (4H-SiC) based on the numerically calculated density of states (DOS) to obtain the electron mobility at low electric fields. From the results, it can be concluded that a correct calculation of the DOS requires a very dense wavevector k-mesh when low electron kinetic energies are considered. The crucial issue is the numerical efficiency of the DOS calculation. We investigate the scaling efficiency when different numbers of cores are used.

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