摘要
Lattice,magneticandorbitalstructuresinKCuF3areself-consistentlydeterminedbyourclusterself-consistentfieldapproachbasedonaspin-orbital-latticeHamiltonian.Twostablestructuresareobtainedandfoundtobedegenerate,whichconfirmsthepresenceofthecoexistentphasesobservedexperimentally.Weclearlyshowthatduetotheinherentfrustration,thegroundstateofthesystemonlywiththesuperexchangeinteractionisdegenerate;whiletheJahn-Tellerdistortion,especiallytheanharmoniceffect,stabilizestheorbitalorderedphaseatabout23%inthex2-y2orbitandat77%inthe3z2-r2orbit.MeanwhilethemagneticmomentofCuisconsiderablyreducedto0.56μB,andmagneticcouplingstrengthsarehighlyanisotropic,Jz/Jxy≈18.Theseresultsareingoodagreementwiththeexperiments,implyingthattheanharmonicJahn-TellereffectplaysanessentialroleinstabilisingtheorbitalorderedgroundstateofKCuF3.
出版日期
2009年10月20日（中国Betway体育网页登陆平台首次上网日期，不代表论文的发表时间）
