Insights on modulating electronic and transport properties of the sawtooth–sawtooth penta-SiC2 nanoribbons under uniaxial small strain by first-principles calculations

Abstract

Based on the density functional theory in combination with the nonequilibrium Green’s function formalism, we study the structural, electronic, and transport properties of SS-pSiC2 NRs under a sequence of uniaxial strains in the range from 10% compression to 10% stretch. The pentagon network of SS-pSiC2 NRs is still maintained, but the bond length along the strained direction is largely changed under this strain. The electronic band structure and bandgap are strongly affected by the uniaxial compressive strain. The evolution of the bandgap vs the strain is linear. With a bias voltage of 2 V, the current of the 10% compressed sample increased 75 times, and the current of the 10% stretched sample increased 2.5 times compared to the one of the relaxed sample. The I–V characteristic of SS-pSiC2 NRs seems to be more sensitive to compressive strain than the stretch strain. Our calculations may indicate new applications of strain structures in electromechanical devices based on SS-pSiC2 NRs.