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arXiv · 1401.4553

Effect of line defects on the electrical transport properties of monolayer MoS$_{2}$ sheet

Amretashis Sengupta·Dipankar Saha·Thomas A. Niehaus·Santanu Mahapatra
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Abstract

We present a computational study on the impact of line defects on the electronic properties of monolayer MoS2. Four different kinds of line defects with Mo and S as the bridging atoms, consistent with recent theoretical and experimental observations are considered herein. We employ the density functional tight-binding (DFTB) method with a Slater-Koster type DFTB-CP2K basis set for evaluating the material properties of perfect and the various defective MoS2 sheets. The transmission spectra is computed with a DFTB-Non-Equilibrium Greens Function (NEGF) formalism. We also perform a detailed analysis of the carrier transmission pathways under a small bias and investigate the phase shifts in the transmission eigenstates of the defective MoS2 sheets. Our simulations show a 2-4 folds decrease in carrier conductance of MoS2 sheets in the presence of line defects as compared to that for the perfect sheet.

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Amretashis Sengupta, Dipankar Saha, Thomas A. Niehaus, Santanu Mahapatra. 2014-08-01. Effect of line defects on the electrical transport properties of monolayer MoS$_{2}$ sheet. https://doi.org/10.1109/tnano.2014.2364038

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