فهرست

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

نشریه: تابستان ۱۳۹۷ - مقاله 1   صفحات :  117 تا 124



کد مقاله:
nm-301

مولفین:
فرهاد ستاری


چکیده مقاله:

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.


Article's English abstract:

In this paper, we investigate spin-dependent tunneling time and spin polarization through monolayer graphene superlattice with Rashba spin–orbit interaction in the presence of zigzag and armchair direction strain. It is found that the oscillation amplitude of the dwell time increases by increasing the strain strength. In addition, for the zigzag direction strain the Hartman effect can be observed for the both spin-up and spin-down electrons. When the armchair direction strain is applied to a monolayer graphene the spin polarization increases with increasing the strain strength, whereas for the zigzag direction strain it is zero. In this case, unlike the zigzag direction strain tunneling time for the normal incident angle depends on the spin state of electron.


کلید واژگان:
ابر شبکه، برهمکنش اسپین- مدار راشبا، زمان تونل‌زنی، قطبش‌پذیری اسپینی، گرافین تحت کرنش.

English Keywords:
Superlattice; Rashba spin–orbit interaction; Tunneling time; Spin polarization; Strained graphene.

منابع:

English References:
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