Contents
Define crystal structure of Sr3Fe2O7
SrF = sw; SrF.genlattice('lat_const', [3.8 3.8 20.4],'sym','I 4/m m m') SrF.addatom('r',[0 0 0.0972],'S',2,'label','MFe4','color','blue') SrF.gencoupling
Undefined function or variable 'sw'. Error in tutorial23 (line 3) SrF = sw;
define magnetic Hamiltonian
Value of the exchange constants
J1 = -7.20; Jc1 = -5.10; J2 = 1.05; J3 = 2.10; Jc3 = 0.01; D = diag([0 0 -0.06]); SrF.addmatrix('label','J1', 'value',J1, 'color','red') SrF.addmatrix('label','Jc1','value',Jc1,'color','orange') SrF.addmatrix('label','J2', 'value',J2, 'color','white') SrF.addmatrix('label','J3', 'value',J3, 'color','gray') SrF.addmatrix('label','Jc3','value',Jc3,'color','yellow') SrF.addmatrix('label','D', 'value',D, 'color','purple') % to add the two ion coupling SrF.addcoupling('J1',1) SrF.addcoupling('Jc1', 2) SrF.addcoupling('J2',3) SrF.addcoupling('J3',7) SrF.addcoupling('Jc3',6) SrF.addaniso('D') % Define magnetic structure S0 = [0 -1.162 0 -1.162; 0 1.162 0 1.162;2 -1.140 2 -1.140]; SrF.genmagstr('mode','helical','S',S0,'k',[1/7 1/7 1],'n',[1 1 0]) %SrF.optmagsteep SrF.plot('coplanar',0.1)
Plot figure
figure nHkl = 501; Evect = 0:0.5:35; % Fig. 3(f) subplot(1,5,1) specFerr = SrF.spinwave({[0.6 0.14 0] [1.4 0.14 0] nHkl},'hermit',false); specFerr = sw_magdomain(specFerr,'axis',[0 0 1],'angled',[0 90 180 270]); specFerr = sw_neutron(specFerr); specFerr = sw_egrid(specFerr,'Evect',Evect); specFerr = sw_instrument(specFerr,'Ei', 40,'dE',1.72,'dQ',0.05,'norm',false); sw_plotspec(specFerr,'mode','color','legend',false,'axLim',[0 0.6]); colormap(jet) % Fig. 3(g) subplot(1,5,2) specFerr = SrF.spinwave({[0.6 -0.4 0] [1.4 0.4 0] nHkl},'hermit',false); specFerr = sw_magdomain(specFerr,'axis',[0 0 1],'angled',[0 90 180 270]); specFerr = sw_neutron(specFerr); specFerr = sw_egrid(specFerr,'Evect',Evect); specFerr = sw_instrument(specFerr,'Ei', 40,'dE',1.72,'dQ',0.05,'norm',false); sw_plotspec(specFerr,'mode','color','axLim',[0 0.2],'legend',false) colormap(jet) % Fig. 3 (h) subplot(1,5,3) specFerr = SrF.spinwave({[-0.4 -0.4 5] [0.4 0.4 5] nHkl},'hermit',false); specFerr = sw_magdomain(specFerr,'axis',[0 0 1],'angled',[0 90 180 270]); specFerr = sw_neutron(specFerr); specFerr = sw_egrid(specFerr,'Evect',Evect); specFerr = sw_instrument(specFerr,'Ei',20,'dE',0.012,'dQ',0.0167,'norm',false); sw_plotspec(specFerr,'mode',3,'axLim',[0 0.5],'legend',false) colormap(jet) % Fig. 3 (i) subplot(1,5,4) specFerr = SrF.spinwave({[-0.4 -0.4 5] [0.4 0.4 5] nHkl},'hermit',false); specFerr = sw_magdomain(specFerr,'axis',[0 0 1],'angled',[0 90 180 270]); specFerr = sw_neutron(specFerr); specFerr = sw_egrid(specFerr,'Evect',Evect); resMat = [0 10 20 30 40 50 60;6 4.5 3.25 2.12 1.15 0.4 0]'; specFerr = sw_instrument(specFerr,'Ei', 60,'dE',resMat,'dQ',0.05, 'norm',false); sw_plotspec(specFerr,'mode',3,'axLim',[0 0.2],'legend',false) colormap(jet) axis([0.0 0.8 7 28]); % Fig. 3 (j) subplot(1,5,5) specFerr = SrF.spinwave({[-0.4 -0.4 7] [0.4 0.4 7] nHkl},'hermit',false); specFerr = sw_magdomain(specFerr,'axis',[0 0 1],'angled',[0 90 180 270]); specFerr = sw_neutron(specFerr); specFerr = sw_egrid(specFerr,'Evect',Evect); specFerr = sw_instrument(specFerr,'Ei', 60,'dE',resMat,'dQ',0.05, 'norm',false); sw_plotspec(specFerr,'mode','color','axLim',[0 0.2],'legend',false) colormap(jet) axis([0.0 0.8 8 35]);