003512[2]

(1)()OBC:CD: DE: CDEFGC:

(2)TcTc

HcHcHc

(BH)max (http://www.aacg.bham.ac.uk/magnetic_materials/history.htm)

()3d4f

3d Fe, Co, NiMn (MnAs, MnSb, MnBi, MnAl, MnGa, Mn5Ge3, PtMnBi), Cr (CrO2, Cr3Te4, CdCr2Se4)4fGd, Dy

3dTi V Cr () TN=308KMn() TN=100K@RTFe m=2.219 B/atom Tc=1043KCo m=1.715 B/atom Tc=1388KNi m=0.604 B/atom Tc=631KCu

4fGd3d

SmCo5NdFe2B14GdCoTbFe

Ce12.5Pr25Nd19Sm14.8Eu90Gd293Tb222229Dy85179Ho20131Er2084

(Wb/cm2) HPhttp://www.magnet.okayama-u.ac.jp/magword/domain/

-e[C]a[m]v[m/s] 2a/v[s] i=-ev/2a[A]i S= a2 =iS=-eav/2=mav =-(e/2m) N

S

l=LL=-(e/2m) l=-(e/2m)L=- BL B=e/2m =9.2710-24[J/T][J/T]=[Wb2/m]/[Wb/m2]=[Wbm]

s1/2sz1/2 s=ss=-(e/m)ss=-(e/m)s=- 2Bs2g(g=2.0023) s=- gBs

Na()D

NaDD13s1/23p1/2D23s1/23p3/2http://hyperphysics.phy-astr.gsu.edu/hbase/quantum/sodzee.html#c3

n=1 K-shelln=2 L-shelln=3 M-shell1s 22s, 2p 2+63s, 3p, 3d 2+6+10=18

nl=n-1, .... ,0

s, p, d, fl=0, 1, 2, 3s0

L, S(n, l, ml, ms)1(Pauli)SLsl(Hund1)S(Hund2)Jless than halfJ=|L-S| more than halfJ=L+S

3d4f

()()() MM=( n- n)B

TcTCTN

M-TJS=1/2,1,

(demagnetization field)Mn = Mn(Wb/m2) /0NNMM

N (Nx, y, zNx, Ny, NzHdi=-NiMi/0 (i=x,y,z)Nx, Ny, NzNx+ Ny+ Nz=1Nx= Ny= Nz=1/3zNx= Ny= 1/2Nz=0Nx= Ny= 0Nz=1 Heff=Hex-NM/0 xyzzxyzxyNz=1Nx= 0Ny= 0Nx= 1/2Ny= 1/2Nx=1/3Ny=1/3Nz=1/3Nz=0

MHd U=MHdHMT T=-MH sinEU=Td= - 0MH sin d=MH (1-cos) U=-MH H=-Hd U=MHd

xyz=0zxd =Is 2md

()

[100][111]xyz[111][100][110]

(magnetic domain)NS

(Fe[001])[001](001)[100][010][-100][0-10]90[111]()

WeissP.Weiss: J. Phys. 6, 661 (1907)H. Barkhausen: Phys. Z. 20, 401 (1919)

micromagnetics[W.F.Brown, Jr.; J. Appl. Phys. 11, 160 (1940), Phys. Rev. 58, 736 (1940) ]UmagUexUaUelU=Umag+Uex+Ua+Uel

Gyromagnetic constant: Damping constantHeff: Effective fieldMs: Saturation magnetizationMs=|M|,

Micromagnetic simulation using LLG Hy = 10 kOe 0 Oe divMdivMy Dot model

Saturation magnetization (Ms)800 emu/cm3Exchange field (A)110-6 erg/cm3Anisotropic constant (Ku)1000 erg/cm3Gyro magnetic constant)-1.76107 rad/(sOe)Damping constant0.2Easy axisY directionDot Size200 nm200 nm100 nmNumber of dot1Mesh size10 nm10 nm10 nm

200 x 200 x t50 nm- dv M200 x 200 x t100 nm

Force gradient imageSpin distribution image

Low-moment tip(CoPtCr/240 in HV)High-moment tip(CoPtCr/500 in Air)Spin distribution imageMFM

Hy = 10 kOe 0 Oe Dot modeldivMdivMy

Saturation magnetization (Ms)800 emu/cm3Exchange field (A)110-6 erg/cm3Anisotropic constant (Ku)1000 erg/cm3Gyro magnetic constant)-1.76107 rad/(sOe)Damping constant0.2Easy axisY directionDot Size200 nm200 nm100 nmNumber of dot1Mesh size10 nm10 nm10 nm

Dot model

Graph3

792.108035

761.845559

560

205.70034

111.242521

31.31431

10.901125

-9.698591

-95.156627

-221.06158

-560

-761.780267

-796.814957

-761.780262

-580

-206.635844

-111.24205

-31.314309

-10.901066

E.A.

H (Oe)

M (emu/cc)

testHy

TitleHx(Oe)Hy(Oe)Hz(Oe)|H|(Oe)Mx(emu/cc)My(emu/cc)Mz(emu/cc)|M|(emu/cc)

test-Hy10000.0100000100000792.1080350792.108035

test-Hy5000.05000050000761.8455590761.845559

3000560

test-Hy1000.01000010000.193714205.70034-0.361489205.700749

test-Hy500.050005000111.2425210111.242521

test-Hy100b.01000100031.31431031.31431

test-Hy0.0000010.901125010.901125

test-Hy-100.0-10001000-9.69859109.698591

test-Hy-500.0-50005000-95.156627095.156627

test-Hy-1000.0-1000010000-221.061580221.06158

-3000-560

test-Hy-5000.0-5000050000-761.7802670761.780267

test-Hy-10000.0-100000100000-796.8149570796.814957

test-Hy_-10k_-5k.0-5000050000-761.7802620761.780262

-3000-580

test-Hy_-10k_-1k.0-1000010000.000155-206.635844-0.000024206.635844

test-Hy_-10k_-5000-5000500-0.000016-111.24205-0.000007111.24205

test-Hy_-10k_-1000-10001000-31.314309031.314309

test-Hy_-10k_000000-10.901066010.901066

Ms800

Ku1000

Hk2.5

Hk=2Ku/Ms

testHy

E.A.

H (Oe)

M (emu/cc)

H (Oe)

M (emu/cc)

Graph1

792.108035

761.845559

560

205.70034

111.242521

31.31431

10.901125

-9.698591

-95.156627

-221.06158

-560

-761.780267

-796.814957

-761.780262

-580

-206.635844

-111.24205

-31.314309

-10.901066

H (Oe)

M (emu/cc)

P1-Crs

TitleHx(Oe)Hy(Oe)Hz(Oe)|H|(Oe)Mx(emu/cc)My(emu/cc)Mz(emu/cc)|M|(emu/cc)

P1-Crs_L500n-W100n-t50n_10x10x10_a02_Hz20k00200002000000798.8078661797747.318844

P1-Crs_L500n-W100n-t50n_10x10x10_a02_Hz10k00100001000000794.012011787106.133157

P1-Crs_L500n-W100n-t50n_10x10x10_a02_Hz5k00500050000.933771-8.07547680.0378711531397.331096

P1-Crs_L500n-W100n-t50n_10x10x10_a02_Hz1k0010001000-0.1029510.186052174.124484393007.993059

P1-Crs_L500n-W100n-t50n_10x10x10_a02_Hz0000000-0.09572219127.439362

P1-Crs_L500n-W100n-t50n_10x10x10_a02_Hz_-50000-50050000-79.241447180525.944069

P1-Crs_L500n-W100n-t50n_10x10x10_a02_Hz_-1k00-1000100000-174.142919393049.521032

P1-Crs

=m+w

18090

(demagnetization field)HM

FIBCoCrPt(500nm)MFM (M)CoCrPt

(vortex)(200nm)MFM ()

(closure domain)(1m)MFM (M2)D2 MFM

MFM()(Fe20Ni80) (M)

FIBCo ()200nm1m, 200nm

(magnetic recording)

1898V.Poulsen()19001921L.De Forest()1930

(, 1991)5.18

)=v/f (v:, f:)

E()(, 1991)5.19, 5.20

2MR()(MR:)AMR()90GMR()

GMRF1F2GMR(SV)

GMR()(F)/(N)/(F2)F1, F2

NiFe(free)/Cu/NiFe(pinned)/AF(FeMn) ( FeMn)SAF

HDHD1992MR25%(1010)60%(10100)1997GMR100%(101000)40Gb/in2AFC()2003150 Gb/in22004200 Gb/in2

HDHD1992MR25%(1010)60%(10100)1997GMR100%(101000)40Gb/in2AFC()2003150 Gb/in22004200 Gb/in2

197019901010199010100100Gb/in22000

CoCrTaCo

nmCoCrCr 10 nm

CoCrPtBCoCrCoCrCrKuV (KuV)kT

20 Gb/in210 nmp.97(2003)

=KuV/kT>60MSJp.97(2003)

=KuV/kT>60DdD-1/2Vd3VDD-3/2KuHcHc=2Ku/MsD3/2[1]Hc [1] T.W. McDaniel and W.A. Challener: Proc. MORIS2002, Trans Magn. Soc. Jpn. 2 (2002) 316.

AFC()AFC(antiferromagnetically coupled media)RuVSF(synthetic ferromagnet)

(AFC)AFC

500Gbits/in21/2

HcHc

HDDCoCrMOMOPt/CoHcHc

CoCrPt layerresist grooveby imprinting80nm-pitch, 40nmf()