Journal of Interfaces, Thin Films, and Low dimensional systems

Josephson current for a Graphene nanoribbon using a lattice model

Document Type : Original Article

Authors

1 Physics Departement, Alzahra University, Tehran, Iran

2 Physics Department, Physics and Chemistry Faculty, Alzahra University, Tehran, Iran

3 Physics Department, Alzahra University, Tehran, Iran

4 Department of Physics, Sharif University of Technology, Tehran, Iran

Abstract

A tight binding approach based on the Bogoliubov-de Gennes approach has been used to calculate the DC Josephson current for a lattice model for S-GNR-S junctions , for short junctions with respect to superconducting coherence length. We calculate the phase, length, width and chemical potential dependence at the Josephson junction and discuss the similarities and differences with regard to the theoretical and experimental results obtained for graphene. To make calculations on graphene, using a lattice model, we convert the graphene honeycomb structure to a brick lattice structure that does not change the lattice topology. Then, by removing several atoms from the lattice , we create the simple vacancy defects in the brick lattice and we also calculate Josephson current in the apparance of these vacancies .

Keywords

Main Subjects

Article Title [Persian]

جریان جوزفسون برای نانوریبون گرافینی با استفاده از مدل شبکه ای

Authors [Persian]

  • سمیه زارعی 1
  • وحید دادمهر 2
  • حسین حکیمی پژوه 3
  • زهرا فرائی 4

1 گروه فیزیک دانشگاه الزهرا

2 گروه فیزیک، دانشکده فیزیک و شیمی، دانشگاه الزهرا

3 گروه فیزیک دانشگاه الزهرا

4

Abstract [Persian]

یک روش بستگی قوی برپایه روش Bogoliubov – de Gennes برای محاسبه جریان جوزفسون DC مربوط به یک مدل شبکه ای برای پیوندگاه های S – GNR – S ، برای پیوندگاه های کوتاه نسبت به طول همدوسی ابررسانشی ، بکاربرده شده است. ما وابستگی به فاز ، طول ، پهنا و پتانسیل شیمیایی را در پیوندگاه جوزفسون محاسبه می کنیم و شباهت ها و اختلافات بدست آمده با توجه به نتایج نظری و تجربی حاصل شده برای گرافین را بحث می کنیم. برای انجام محاسبات بر روی گرافین با استفاده از مدل شبکه ای ، ساختار لانه زنبوری گرافین را به ساختار شبکه آجرمانند تبدیل می کنیم که این تبدیل توپولوژی شبکه را تغییر نمی دهد. سپس با برداشتن چند اتم از شبکه ، تهی جاهای ساده را در شبکه آجری ایجاد می کنیم و جریان جوزفسون را در حضور این تهی جاها نیز محاسبه می کنیم.

Keywords [Persian]

  • اثر جوزفسون
  • مدل شبکه ای
  • نانوریبون گرافینی
  • تهی جا
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Journal of Interfaces, Thin Films, and Low dimensional systems
Volume 2, Issue 1
November 2018
Pages 113-121