Masu bincike daga NTNU suna haskaka kayan maganadisu a ƙananan sikelin ta hanyar ƙirƙirar fina-finai tare da taimakon wasu hasken X-ray masu haske sosai.
Erik Folven, daraktan ƙungiyar lantarki ta oxide a Sashen Tsarin Lantarki na NTNU, da abokan aikinsa daga Jami'ar NTNU da Ghent da ke Belgium sun shirya don ganin yadda ƙananan ƙwayoyin cuta masu sirara ke canzawa lokacin da aka dame su da wani filin maganadisu na waje. An buga aikin, wanda NTNU Nano da Majalisar Bincike ta Norway suka ba da kuɗi kaɗan, a cikin mujallar Physical Review Research.
Ƙananan maganadisu
Einar Standal Digernes ya ƙirƙiro ƙananan maganadisu masu siffar murabba'i da aka yi amfani da su a gwaje-gwajen.
Ƙananan maganadisu masu murabba'i, waɗanda ɗan takarar NTNU Ph.D. Einar Standal Digernes ya ƙirƙira, faɗinsu micromita biyu ne kawai kuma an raba su zuwa yankuna huɗu masu siffar murabba'i, kowannensu yana da yanayin maganadisu daban-daban da ke nuna agogon agogo ko kuma akasin agogon agogo.
A wasu kayan maganadisu, ƙananan ƙungiyoyin atom suna haɗuwa zuwa yankuna da ake kira domains, inda duk electrons ɗin ke da irin wannan yanayin maganadisu.
A cikin maganadisu na NTNU, waɗannan yankuna suna haɗuwa a tsakiyar wuri - tsakiyar vortex - inda lokacin maganadisu ke nuna kai tsaye a ciki ko waje da saman kayan.
"Idan muka yi amfani da filin maganadisu, ƙarin waɗannan yankuna za su nuna hanya ɗaya," in ji Folven. "Suna iya girma kuma suna iya raguwa, sannan kuma za su iya haɗuwa cikin juna."
Electrons kusan a saurin haske
Ganin faruwar hakan ba abu ne mai sauƙi ba. Masu binciken sun ɗauki ƙananan magnet ɗinsu zuwa wani sinadari mai siffar donut mai faɗin mita 80, wanda aka sani da BESSY II, a Berlin, inda ake ƙara yawan electrons har sai sun yi tafiya a kusan saurin haske. Waɗannan electrons masu saurin motsi sannan suna fitar da hasken X-ray mai haske sosai.
"Muna ɗaukar waɗannan hasken X-ray ɗin kuma muna amfani da su a matsayin hasken da ke cikin na'urar hangen nesa," in ji Folven.
Saboda electrons suna tafiya a kusa da synchrotron a cikin gungu da aka raba ta hanyar nanoseconds biyu, X-rays ɗin da suke fitarwa suna zuwa cikin takamaiman bugun jini.
Na'urar hangen nesa ta X-ray mai daukar hoton X-ray, ko STXM, tana ɗaukar waɗannan hasken X don ƙirƙirar hoton tsarin maganadisu na kayan. Ta hanyar haɗa waɗannan hotunan tare, masu binciken za su iya ƙirƙirar fim da ke nuna yadda micromagnet ke canzawa akan lokaci.
Da taimakon STXM, Folven da abokan aikinsa sun dagula ƙananan magnet ɗinsu da bugun wutar lantarki wanda ya samar da filin maganadisu, kuma suka ga yankunan sun canza siffa kuma tsakiyar vortex ɗin ya motsa daga tsakiya.
"Kana da ƙaramin maganadisu, sannan ka huda shi ka yi ƙoƙarin ɗaukar hotonsa yayin da yake sake lanƙwasawa," in ji shi. Bayan haka, sun ga tsakiyar yana komawa tsakiya—amma a kan hanyar da ke lanƙwasa, ba layi madaidaiciya ba.
"Zai yi rawa kamar yadda yake a tsakiya," in ji Folven.
Zamewa ɗaya kuma ya ƙare
Wannan saboda suna nazarin kayan epitaxial, waɗanda aka ƙirƙira a saman wani abu wanda ke ba masu bincike damar gyara halayen kayan, amma zai toshe X-ray a cikin STXM.
A lokacin da suke aiki a NTNU NanoLab, masu binciken sun magance matsalar substrate ta hanyar binne micromagnet ɗinsu a ƙarƙashin wani Layer na carbon don kare halayen maganadisu.
Sai suka yi amfani da hankali da kuma daidai wajen yanke tushen da ke ƙasa da harsashin gallium har sai da wani siririn Layer ya rage. Tsarin aiki mai wahala zai iya ɗaukar awanni takwas a kowane samfurin - kuma zamewa ɗaya na iya haifar da bala'i.
"Abin da ya fi muhimmanci shi ne, idan ka kashe maganadisu, ba za mu san hakan ba kafin mu zauna a Berlin," in ji shi. "Dabara ita ce, ba shakka, a kawo samfura fiye da ɗaya."
Daga kimiyyar lissafi ta asali zuwa na'urori na gaba
Abin godiya ya yi aiki, kuma ƙungiyar ta yi amfani da samfuran da aka shirya da kyau don zana yadda yankunan micromagnet ke girma da raguwa akan lokaci. Sun kuma ƙirƙiri kwaikwayon kwamfuta don fahimtar ƙarfin da ke aiki sosai.
Baya ga haɓaka iliminmu game da kimiyyar lissafi ta asali, fahimtar yadda maganadisu ke aiki a waɗannan ma'aunin tsayi da lokaci zai iya taimakawa wajen ƙirƙirar na'urori na gaba.
An riga an yi amfani da maganadisu don adana bayanai, amma a halin yanzu masu bincike suna neman hanyoyin da za su ƙara amfani da shi. Misali, ana iya amfani da yanayin maganadisu na tsakiyar vortex da yankunan micromagnet don ɓoye bayanai a cikin nau'in 0s da 1s.
Masu binciken yanzu suna da niyyar maimaita wannan aikin da kayan hana ferromagnetic, inda tasirin net na lokutan maganadisu ke ɓacewa. Waɗannan suna da kyau idan ana maganar kwamfuta - a ka'ida, ana iya amfani da kayan hana ferromagnetic don yin na'urori waɗanda ba sa buƙatar kuzari kaɗan kuma suna da ƙarfi ko da lokacin da aka rasa wutar lantarki - amma yana da wahala a bincika saboda siginar da suke samarwa za ta yi rauni sosai.
Duk da wannan ƙalubalen, Folven yana da kyakkyawan fata. "Mun rufe matakin farko ta hanyar nuna cewa za mu iya yin samfura mu kuma duba su da X-ray," in ji shi. "Mataki na gaba zai kasance don ganin ko za mu iya yin samfuran inganci masu kyau don samun isasshen sigina daga kayan hana ferromagnetic."
Lokacin Saƙo: Mayu-10-2021