اثر کرنش بر روی زمان تونل‌زنی و قطبش‌پذیری اسپینی در ابرشبکه‌ی گرافینی

نویسنده

گروه فیزیک، دانشکده علوم دانشگاه محقق اردبیلی، اردبیل

چکیده

در این مقاله زمان تونل زنی وابسته به اسپین و قطبش پذیری اسپینی را در یک ابرشبکه‌ی تک لایه‌ی گرافینی با برهمکنش اسپین - مدار راشبا در حضور کرنش در راستای زیگزاگ و دسته صندلی بررسی می‌کنیم. مشاهده می‌شود دامنه‌ی نوسان زمان تونل زنی با افزایش قدرت کرنش افزایش می‌یابد. علاوه بر این زمانی که کرنش در راستای زیگزاگ باشد اثر هارتمن برای اسپین بالا و پایین قابل مشاهده خواهد بود. برای کرنش در راستای دسته صندلی قطبش پذیری اسپینی با افزایش قدرت کرنش زیاد می‌شود در حالی که قطبش پذیری اسپینی برای کرنش زیگزاگ صفر است. وقتی کرنش در راستای دسته صندلی باشد بر خلاف کرنش در راستای زیگزاگ زمان تونل زنی برای فرود عمود به اسپین الکترون وابسته خواهد بود.

کلیدواژه‌ها


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