کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
1331085 978992 2010 7 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Nitrogen vacancy and ferromagnetism in Cr-doped GaN: First-principles calculations
موضوعات مرتبط
مهندسی و علوم پایه شیمی شیمی معدنی
پیش نمایش صفحه اول مقاله
Nitrogen vacancy and ferromagnetism in Cr-doped GaN: First-principles calculations
چکیده انگلیسی

Nitrogen defects and their effect on the ferromagnetism (FM) in Cr-doped GaN have been systematically investigated by first-principles. Four considered configurations including one N vacancy (VN), single substitutional Cr, double substitutional Cr, and complex of Cr–VN are all ferromagnetic. The lowest energy arrangements for double Cr-doped (or Cr–VN) GaN occur at the nearest Cr–Cr (or Cr–VN) distance. One Cr contributes 84.3% of the total magnetic moment (2.533 μB), while one Cr–Cr pair leads to 5.998 μB moment (more than twice moment of one Cr) by the strong d–d spin coupling, which is mediated by two Cr 3d states antiferromagnetically coupling with the “commonly shared” N 2p states, and driven by a double exchange mechanism. The VN can enhance the FM by adding about 1 μB to the Cr moment but reduce the FM spin exchange interaction between the nearest Cr–Cr pairs, so experimentally, high-performance samples may be synthesized by controlling N pressure.

Nitrogen defects and their effect on the ferromagnetism in Cr-doped GaN were investigated by first-principles. Given are the PDOS of Ga36N36 with one Cr–Cr pair and one complex of Cr–VN.Figure optionsDownload as PowerPoint slide

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Journal of Solid State Chemistry - Volume 183, Issue 11, November 2010, Pages 2662–2668
نویسندگان
, , , , , , ,