Magneto-electronic properties and carrier mobility in phagraphene nanoribbons: A theoretical prediction

To explore the quantum confinement and edge state effects for phagraphene, a recently proposed new 2D material, we here consider to cut it along a certain direction, and six kinds of the nanoribbons with special A-, B- and C-type edge structures are achieved. Their structural stability with H passivation is verified by the calculated binding energy, phonon dispersion and molecular dynamics simulation. The nanoribbons with two A-type edge structures are nonmagnetic semiconductors with a periodically altered band-gap versus the width. While those with B-type and/or C-type edge structure for two edges are spin-degenerate/spin-splitting semiconductors in the antiferromagnetic ground state. Particularly, nanoribbons with A-type edge structure for one edge while with B-type or C-type edge structure for other edge only hold the ferromagnetic ground state and present the bipolar magnetic semiconducting nature. The further studies reveal that the nanoribbon is an excellent magnetoelectric material and its half-metallicity can be realized by the application of an electric field. More interestingly, the carrier mobility for the nanoribbon with two A-type edge structures is very high and strikingly size-dependent, from ∼103 to 106 cm2/V.S. This means that width control is a possible routine to effectively regulate the mobility of nanoribbons.

Structural stability, magneto-electronic properties and carrier mobility for phagraphene nanoribbons are investigated in depth, and numerous unusual and unique behaviors for such nanoribbons are predicted.194