Cov xwm txheej rau ferromagnetism hauv kev ua cov khoom sib nqus

Ferromagnetism hais txog qhov tseeb tias lub sijhawm sib nqus ntawm cov atoms uas nyob ib sab lossis ions nyob rau hauv ib yam khoom yog roughly aligned in the same direction in some regions because of their interactions. Thaum lub zog magnetic teb siv tau nce, lub sijhawm sib nqus sib nqus ntawm cov cheeb tsam no tau ua raws. yuav nce mus rau ib qho kev txwv. Dab tsi yog cov xwm txheej rau kev ua cov ferromagnetism hauv cov khoom sib nqus?

1. Yuav tsum muaj lub plhaub tsis muaj hluav taws xob nyob hauv lub atom;

2, thiab qhov piv ntawm Rab / r ntau dua 3 ua rau kev sib pauv ib qho zoo. Qhov qub txhais tau hais tias lub sijhawm sib nqus ntawm lub cev ntawm lub atom tsis yog xoom; qhov kawg txhais tau hais tias yuav tsum muaj ib qho qauv siv lead ua.

Raws li cov txheej txheem thiab txoj kev xav ntawm spontaneous magnetization, ntau yam ferromagnetic muaj peev xwm piav qhia. Piv txwv li, qhov cuam tshuam ntawm qhov kub thiab txias ntawm ferromagnetism. Thaum qhov kub thiab txias, qhov sib txawv ntawm atomic nce, uas txo cov txiaj ntsig pauv, thiab qhov kev taw qhia tsis tu ncua ntawm atomic magnetic lub sij hawm yog tsis tu ncua los ntawm thermal motion, yog li cov spontaneous magnetization Ms txo.

Txog thaum qhov kub siab tshaj qhov Curie point, qhov kev taw qhia tsis tu ncua ntawm atomic magnetic lub sij hawm raug rhuav tshem tag nrho, lub sijhawm sib nqus tsis muaj nyob, thiab cov khoom hloov pauv ntawm ferromagnetic mus rau paramagnetic. Tsis tas li ntawd, magnetocrystalline anisotropy, magnetostriction, thiab lwm yam tuaj yeem piav qhia.