Simple correction to bandgap problems in IV and III–V semiconductors: an improved, local first-principles density functional theory

Abstract

We report results from a fast, efficient and first-principles full-potential N th -order muffin-tin orbital (FP-NMTO) method combined with van Leeuwen-Baerends correction to local density approximation exchange-correlation potential. We show that more complete and compact basis set is critical in improving the electronic and structural properties. We exemplify the self-consistent (non-relativistic) FP-NMTO calculations on group IV and III-V semiconductors. Notably, predicted bandgap, lattice constant, and bulk modulus are in good agreement with experiments (e.g., for Ge we find 0.86 eV, 5.57Å, 75 GPa vs. measured: 0.74 eV, 5.66Å, 77.2 GPa). We also showcase its application to the electronic properties of 2-dimensional h−BN and h−SiC, again finding good agreement with experiments. arXiv:1807.07606v3 [cond-mat.mtrl-sci]

Semiconductor Physics: A Density Functional Journey

“…This is utilised by Datta et al by incorporating the original vLB potential in self-consistent FP-NMTO method which produces almost exact bandgaps for traditional group IV (Si, Ge) and group III-V (GaAs, InP, etc.) semiconductors [22]. This method is as fast as any other GGA.…”

“…For that no sum is needed in Eq. [22] and 𝑖, 𝑗, 𝑘, 𝜎 = 1 in the definition of Fermi hole and density, so, for this special case 𝜌 𝑥 (r, r )| 1 = − 𝜌(r )| 1 and the exchange energy…”

“…This method is as fast as any other GGA. So, this type of potential-only correction which is not coming from any functional derivative of energy can also provide better electronic structure prediction with tricky tuning as in [22,48].…”

“…A comparison of LDA, PBE and vLB xc potential in [100] plane for Ge is presented in Fig. 3 calculated using FP-NMTO method [22]. The LDA potential is smooth, whereas, PBE is showing a variation in the interstitial region (region in-between Ge atoms) and vLB produces larger variation.…”

“…This vLB correction to LDA has found a farm footing with the introduction of self consistent full-potential N-th order muffin tin orbital (FP-NMTO) basis sets. Usng this vLB-FP-NMTO method Datta et al have showed improvement in finding the structural properties and band gaps for orthodox group IV and group III-V materials [22]. This method is further applied on carbon nitrides (C 3 N 4 ) polymorphs and it helped to identify the 𝛾-C 3 N 4 as a better candidate for photocatalysis [14].…”