磁性、超导和量子自旋液体

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S2^5,‡Úþfg^—N-p§‡ÅnïÄp.7Heisenberg.XH=JSi

4、
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5、yH=~kc^~kc^~k+V~k~k0c^~k0"c^~k0#c^~k#c^~k"~k~k~k0Ù¥8><Vj~kjj~k0j!DV~k~k0=>:0j~kj;j~k0j>!D^5,‡Úþfg^—N-p§‡ÅnïÄp.12>fé'é^5,‡Úþfg^—N-p§‡ÅnïÄp.13÷*þfÄ1.BCSÄżêYyyjBCSi=(u~k+~kc^~k"c^~k#)j0i~k2.Sëþ0/h^#(~r)^"(~r)ipi(~r)(~r)=nse^5,‡Úþfg^—N-p§‡ÅnïÄp.14Ginzburg-LandaunØ1.1a(~x)+bj(~x

6、)j2(~x)+(ihreA~)2(~x)=02m2.ehjj2e~js(~x)=r(~x)A~(~x)mh^5,‡Úþfg^—N-p§‡ÅnïÄp.15^ÏþfzIIZhr
d~l=A~
d~l=B~
dS~=eSI
=r
d~l=2nh=n=n0e^5,‡Úþfg^—N-p§‡ÅnïÄp.16>fg^g^ü,S=01=p(j"#ij#"i)2g^n•S=1,Sz=1;0;18>:2j##i^5,‡Úþfg^—N-p§‡ÅnïÄp.172.p§‡N^5,‡Úþfg^—

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8、‡Úþfg^—N-p§‡ÅnïÄp.22‡c^ƒÚ‡ƒ^5,‡Úþfg^—N-p§‡ÅnïÄp.23La2CuO4¬N(^5,‡Úþfg^—N-p§‡ÅnïÄp.24Figure3:Cu3d>fU?3¬

9、¥3^5,‡Úþfg^—N-p§‡ÅnïÄp.25p§‡N¥>fé˜mżêäkdx2y2é¡5Figure4:Tsueietal,Rev.Mod.Phys.72,969^5,‡Úþf