Abstract
Using the full potential based WIEN 2K method, we have explored thickness dependent energy band gaps and effective masses of BN layer sandwiched by graphene (G/BN/G) and graphene sandwiched by BN (BN/G/BN) systems. Here, capping and substrate layer coverages are changed from 1 monolayer (ML) to 2ML and 1 to 4ML, respectively. In G/BN/G systems, we find rather small energy gaps and the energy dispersions become quadratic near the K-point. Unlike in G/BN/G, a trilayer BN/G/BN shows large gap of 117meV and it decreases as the number of BN layer increases, but we still find a gap about 90meV in BN (2ML)/G/BN (4ML) system. The thickness dependent suppression of band gap in BN/G/BN can be nicely interpreted in terms of interlayer distance from BN substrate to graphene. Furthermore, very interestingly, the energy dispersion is nearly linear near the K-point and this linearity is still preserved even in all BN/G/BN systems. Surprisingly, the effective mass decreases as the number of BN layer increases. For instance, the smallest effective mass of 0.00235 me is estimated in conduction band along K−Γ direction. Overall, our calculations may suggest that the BN/G/BN system has potential application for fast radio frequency (RF) device or on-off switching transistor because the linearity and small effective mass is kept without any external factors such as electric field, strain, and doping.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.