Tunable spin and conductance in porphyrin-graphene nanoribbon hybrids

Communications Physics

Article

Fei Gao¹  Mads Brandbyge¹  Rodrigo E. Menchón²  Aran Garcia-Lekue³ 

[1] Department of Physics, Technical University of Denmark, Kongens Lyngby, Denmark;Donostia International Physics Center (DIPC), Donostia-San Sebastián, Spain;Donostia International Physics Center (DIPC), Donostia-San Sebastián, Spain;IKERBASQUE, Basque Foundation for Science, Bilbao, Spain;

关键词: ;   

DOI  :  10.1038/s42005-023-01231-y

 received in 2022-11-23, accepted in 2023-05-03,  发布年份 2023

来源: Springer

【 摘 要 】

Recently, porphyrin units have been attached to graphene nanoribbons (Por-GNR) enabling a multitude of structures. Here we report first-principles calculations of two prototypical, experimentally feasible, Por-GNR hybrids, one of which displays a small band gap relevant as electrodes in devices. Embedding a Fe atom in the porphyrin causes spin-polarized ground state (S = 1). Using density functional theory and nonequilibrium Green’s function, we examine a 2-terminal setup involving a Fe-Por-GNR between small band gap, Por-GNR electrodes. The coupling between the Fe-d and GNR band states results in a Fano anti-resonance feature in the spin transport, making the conductance highly sensitive to the Fe spin state. We demonstrate how mechanical strain or chemical adsorption on the Fe give rise to spin-crossover to S = 2 and S = 0, directly reflected in the transmission. Our results provide a deep understanding which can open an avenue for carbon-based spintronics and chemical sensing.

【 授权许可】

CC BY   
© The Author(s) 2023

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