Study on the electronic structures and transport properties of the polyporphyrin nanoribbons with different edge configurations

• Published in: Physics letters. A 2018-09, Vol.382 (38), p.2769-2775
• Main Authors: Zhang, Shidong, Zhang, Xiaojiao, Li, Mingjun, Zeng, Bowen, Duan, Haiming, Zhang, Dan, Long, Mengqiu
• Format: Article
• Language: English
• Subjects: Bipolar spin-filtering effect; Carbocyclic eight-membered ring; Polyporphyrin nanoribbon; Spin-polarized density functional theory
• ISSN: 0375-9601; 1873-2429
• DOI: 10.1016/j.physleta.2018.07.046

Combining the density functional theory with the non-equilibrium Green's function, three kinds of polyporphyrin nanoribbons (PPNRs) with different edge configurations have been considered: 1) all carbocyclic eight-membered rings (C8-Rs) located in edge are broken (M1); 2) all C8-Rs located in edge are perfect (M2); 3) partial C8-Rs located in edge are broken, subject to two kinds of configurations, as illustrated by M3 and M4. Calculation results indicate that the completeness of the C8-Rs can influence the electronic structures and transport properties of the nanoribbons. M1 is a nonmagnetic indirect semiconductor, while M2 and M3 are magnetic metals, M4 behaves as the bipolar magnetic semiconductor. Moreover, the spin-dependent transport properties of the two-lead devices based on PPNRs show that the significant spin-filtering effect can be realized in the device with partially broken C8-Rs in edge. Our results indicate that the PPNRs based devices would be suitable for spintronics devices. •The electronic structure is closely related with the number of the perfect carbocyclic eight-membered rings (C8-Rs).•The bipolar magnetic semiconductor can be obtained by partially breaking the C8-Rs.•Bipolar spin-filtering effect can be observed in the devices.•The spin-filtering efficiency (SFE) can be improved by partially breaking the C8-Rs.