Hydrogenated group IV-V monolayer HAB6: A new type of Dirac material constructed by isoelectronic rule

The Dirac materials possess characters of massless fermions, ultrahigh carrier mobility, and many other novel features, which make them have significant applications in the massless and dissipationless quantum devices. Here we found that the hydrogenation of semi-conducting PC6 (HPC6) monolayer could produce a new Dirac material. The fully optimized HPC6 monolayer presents a two-dimensional puckered pristine honeycomb structure. The ab initio molecular dynamics simulations and phonon spectra calculations confirm that HPC6 monolayer can maintain good structural integrity at temperatures up to 400 K. The calculation results reveal that the H atoms form strong covalent bond with P atoms and present -1 valence state, the electronic structure calculations show that HPC6 monolayer possess Dirac cone at K point, and the Fermi velocity is up to 106 m/s, which is the same order of magnitude as graphene. The origin of Dirac point could be explained by isoelectronic rule. Based on this, a series of structures of hydrogenated Group IV-V monolayer HAB(6) (A = N, P, As, Sb, Bi; B = C, Si, Ge, Sn) were proposed. Further electronic structure calculations reveal that 16 of them are dynamically stable and belong to Dirac materials.

Automated summary

The hydrogenation of semi-conducting PC6 monolayer can produce a new Dirac material with good structural integrity at high temperatures.