Impact of intrinsic deformations on the negative differential resistance of monolayer MoS$_2$ ultra-short channel MOSFET
Amretashis Sengupta, Santanu Mahapatra
备注：
The authors have found out errors in the paper. The treatment of DFT-NEGF method involved Neumann boundary conditions along the width which effectively reduces the system to that of a nanoribbon, the paper is to be re-written and re-submitted
In this work we present a study on the impact of various intrinsic deformations like ripples, twist, wrap on the electronic properties of ultra-short monolayer MoS2 channels. The effect of deformation (3-7o twist or wrap and 0.3-0.7 buckling amplitude) on a 3.5 nm planar monolayer MoS2 MOSFET is evaluated by the density functional theory and the non-equilibrium Green`s function (DFT-NEGF) approach. We study the channel density of states, transmission spectra and the ID-VD characteristics under the varying conditions, with focus on the negative differential resistance (NDR) behavior. Our results show significant change in the NDR peak to valley ratio (PVR) and the NDR window with such minor intrinsic deformations, especially with the rippling.
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