Spin Hall Nano-Antenna

التفاصيل البيبلوغرافية
العنوان: Spin Hall Nano-Antenna
المؤلفون: Fabiha, Raisa, Pal, Pratap Kumar, Suche, Michael, Mondal, Amrit Kumar, Topsakal, Erdem, Barman, Anjan, Bandyopadhyay, Supriyo
سنة النشر: 2024
المجموعة: Computer Science
Condensed Matter
Physics (Other)
مصطلحات موضوعية: Condensed Matter - Mesoscale and Nanoscale Physics, Electrical Engineering and Systems Science - Systems and Control, Physics - Applied Physics
الوصف: The spin Hall effect is a celebrated phenomenon in spintronics and magnetism that has found numerous applications in digital electronics (memory and logic), but very few in analog electronics. Practically, the only analog application in widespread use is the spin Hall nano-oscillator (SHNO) that delivers a high frequency alternating current or voltage to a load. Here, we report its analogue - a spin Hall nano-antenna (SHNA) that radiates a high frequency electromagnetic wave (alternating electric/magnetic fields) into the surrounding medium. It can also radiate an acoustic wave in an underlying substrate if the nanomagnets are made of a magnetostrictive material. That makes it a dual electromagnetic/acoustic antenna. The SHNA is made of an array of ledged magnetostrictive nanomagnets deposited on a substrate, with a heavy metal nanostrip underlying/overlying the ledges. An alternating charge current passed through the nanostrip generates an alternating spin-orbit torque in the nanomagnets via the spin Hall effect which makes their magnetizations oscillate in time with the frequency of the current, producing confined spin waves (magnons), which radiate electromagnetic waves (photons) in space with the same frequency as the ac current. Despite being much smaller than the radiated wavelength, the SHNA surprisingly does not act as a point source which would radiate isotropically. Instead, there is clear directionality (anisotropy) in the radiation pattern, which is frequency-dependent. This is due to the (frequency-dependent) intrinsic anisotropy in the confined spin wave patterns generated within the nanomagnets, which effectively endows the "point source" with internal anisotropy.
نوع الوثيقة: Working Paper
URL الوصول: http://arxiv.org/abs/2408.08368
رقم الأكسشن: edsarx.2408.08368
قاعدة البيانات: arXiv