کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
1798157 1524815 2016 7 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Discovery of room-temperature spin-glass behaviors in two-dimensional oriented attached single crystals
ترجمه فارسی عنوان
کشف رفتار چرخشی شیشه ای در دمای اتاق در کریستال های متصل به دو بعدی
کلمات کلیدی
موضوعات مرتبط
مهندسی و علوم پایه فیزیک و نجوم فیزیک ماده چگال
چکیده انگلیسی


• Room-temperature spin-glass state was found in 2D oriented attached single crystals.
• Coercivity values were found to be almost invariable at different temperatures.
• The spin topographic map was assumed as SPM “islands” isolated by SG-like “bridges”.

In this study, room-temperature spin-glass behaviors were observed in flake-like oriented attached hematite (α-Fe2O3) and iron phosphate hydroxide hydrate (Fe5(PO4)4(OH)3·2H2O) single crystals. Remarkably, their coercivity (HC) values were found to be almost invariable at various given temperatures from 5 to 300 K. The spin topographic map in these flakes was assumed as superparamagnetic (SPM) “islands” isolated by spin glass (SG)-like “bridges”. A spin-glass model was then proposed to demonstrate the spin frustration within these “bridges”, which were formed by the staggered atomic planes in the uneven surfaces belonging to different attached nanoparticles. Under the spatial limitation and coupling shield of these “bridges”, the SPM “islands” were found to be collectively frozen to form a superspin glass (SSG) state below 80 K in weak applied magnetic fields; whereas, when strong magnetic fields were applied, the magnetic coupling of these “islands” would become superferromagnetic (SFM) through tunneling superexchange, so that, these SFM spins could antiferromagnetically couple with the SG-like “bridges” to yield pronounced exchange bias (EB) effect.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Journal of Magnetism and Magnetic Materials - Volume 406, 15 May 2016, Pages 1–7
نویسندگان
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