橫向磁場中自旋波激發(fā)的微觀機制.pdf

1、華中科技大學(xué)碩士學(xué)位論文橫向磁場中自旋波激發(fā)的微觀機制姓名：李恒甫申請學(xué)位級別：碩士專業(yè)：凝聚態(tài)物理指導(dǎo)教師：商育民20070601華中科技大學(xué)碩士學(xué)位論文IIAbstractThespinwaveisacollectiveeffectofthespins.Itisaveryimptantphysicalquantityofthematerialmagism.Thespinwaveexcitationisausefulmethod.So

2、thespinwaveexcitationsisanattractivetopicinphysicalfields.Themicrocosmicmechanismisaninterimatteratheeticalfoundationofthespinwaveexcitations.Themagicfieldisessentialtothespinwaveexcitations.Therearemuchattentionfocusedo

3、nmagicfieldparallelingzaxis(thespontaneousmagization’sdirection)whilethetransversemagicfieldisusuallyigned.Thisthesisemphasizedontheeffectofthetransversemagicfield.Firstlybyapplyingharmonicoscillatwavefunctionofthespinwa

4、vetheusualequationofthemagizationmotionaprincipleofthespinwave’sevenexcitationswasfond.Secondlyweputthemagicfieldonxyplane(calledthetransversemagicfield)madethemagicfieldunifmrevolvewithzaxisweonlyconsiderthesurfaceofsam

5、plewithoutspinpinningthespinwavefunctioncouldbeexpressedasthefmofthesinefunctionInthecaseoftheassumeconditionwecouldchangedtheangleintothedisplacementwhichisthespinwaveofkm(wavevect)walkparallelingzaxis.Theexpressionisθ=

6、αkmzαisthefactofthefrequencyratio.NotonlytheresultsfromKittel’stheycomputationbutsomenewresultsthroughLLequationwasobtained.Ifamsatisfycertainqualificationsbychoosingthepropervalueofαthequantumnumbermthespinwaveexcitatio