Domain dynamics in Co/Pt/Co/Pt/Co/IrMn M. Czapkiewicz.

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Domain dynamics in Co/Pt/Co/Pt/Co/IrMn M. Czapkiewicz

Transcript of Domain dynamics in Co/Pt/Co/Pt/Co/IrMn M. Czapkiewicz.

Page 1: Domain dynamics in Co/Pt/Co/Pt/Co/IrMn M. Czapkiewicz.

Domain dynamics in Co/Pt/Co/Pt/Co/IrMn

M. Czapkiewicz

Page 2: Domain dynamics in Co/Pt/Co/Pt/Co/IrMn M. Czapkiewicz.

New domain nucleation:N(t)=N0(1-exp(-Rt))

Fatuzzo: cylindric domains nucleation and growth B(t)=

exp(-2k2(1-(1 -(Rt+1/k) +0.5(Rt+1/k)2 –e-Rt(1-1/k) –0.5k2(1-Rt)))

where k=v/Rr,

v i R increase with z H, kconst R=R0exp[-(WN-2HMSVN)/kBT]

v=v0exp[-(WP-2HMSVP)/kBT]

Page 3: Domain dynamics in Co/Pt/Co/Pt/Co/IrMn M. Czapkiewicz.

k: real time

Page 4: Domain dynamics in Co/Pt/Co/Pt/Co/IrMn M. Czapkiewicz.

k: reduced time

Page 5: Domain dynamics in Co/Pt/Co/Pt/Co/IrMn M. Czapkiewicz.
Page 6: Domain dynamics in Co/Pt/Co/Pt/Co/IrMn M. Czapkiewicz.

0 5 10 15-0.2

0.0

0.2

0.4

0.6

0.8

1.0

1.2

- 20 mT- 19.0 mT- 18.7 mT- 18.2 mT- 18.1 mT- 17.5 mT- 17.1 mT- 16.2 mT- 15.6 mT- 15.2 mT- 14.2 mT- 13.3 mT

B [n

orm

aliz

ed

Time [sec]

-100% to -10.5%

0 1 2 3 4 50.0

0.2

0.4

0.6

0.8

1.0

-100% to -10.5%

- 20 mT- 19.0 mT- 18.7 mT- 18.2 mT- 18.1 mT- 17.5 mT- 17.1 mT- 16.2 mT- 15.6 mT- 15.2 mT- 14.2 mT- 13.3 mT

B(t

r)

t/t50

#26 backward

#26 forward

0 10 20 30 40 50 60 700.0

0.2

0.4

0.6

0.8

1.0

- 35.6 mT - 36.2 mT - 36.9 mT - 37.6 mT - 38.3 mT - 39.6 mT

B [N

orm

aliz

ed]

Time [sec]

+ 100% to -21%

0 2 40.0

0.2

0.4

0.6

0.8

1.0

+ 100% to -21%

- 35.6 mT - 36.2 mT - 36.9 mT - 37.6 mT - 38.3 mT - 39.6 mT

B(t

r)

t/t50

Page 7: Domain dynamics in Co/Pt/Co/Pt/Co/IrMn M. Czapkiewicz.

#26 backward

#26 forward

Page 8: Domain dynamics in Co/Pt/Co/Pt/Co/IrMn M. Czapkiewicz.

#26 real time

Page 9: Domain dynamics in Co/Pt/Co/Pt/Co/IrMn M. Czapkiewicz.

#31 forward – without dead time correction

0.0 0.2 0.4 0.6 0.8 1.0 1.2

0.0

0.2

0.4

0.6

0.8

1.0

47,07 mT 35,85 mT 33,92 mT 32,13 mT 30,35 mT 28,56 mT 26,6 mT 24,74 mT 22,89 mT 20,98 mT 18,97 mT 17,06 mT 15,2 mT 13,3 mT 11,4 mT 9,49 mT 7,70 mT 5,79 mT 3,85 mT

Ur [

No

rma

lize

d]

Time [s]

Sample # 31

0.00 0.25 0.50 0.75 1.00 1.25 1.50

0.0

0.2

0.4

0.6

0.8

1.0

47,07 mT 35,85 mT 33,92 mT 32,13 mT 30,35 mT 28,56 mT 26,6 mT 24,74 mT 22,89 mT 20,98 mT 18,97 mT 17,06 mT 15,2 mT 13,3 mT 11,4 mT 9,49 mT 7,70 mT 5,79 mT 3,85 mT

Ur

[No

rma

lize

d]

t/t50

Sample #31

Page 10: Domain dynamics in Co/Pt/Co/Pt/Co/IrMn M. Czapkiewicz.

#31 forward – dead time correction

Page 11: Domain dynamics in Co/Pt/Co/Pt/Co/IrMn M. Czapkiewicz.

#31 forward – fit after dead time correction

Kerr video: for H=21.1mT v=10m/s

Page 12: Domain dynamics in Co/Pt/Co/Pt/Co/IrMn M. Czapkiewicz.

#31 forward – before dead time correction – impossible to fit

Page 13: Domain dynamics in Co/Pt/Co/Pt/Co/IrMn M. Czapkiewicz.

#31 backward – fit after dead time correction

Kerr video: for H=7.8mT v=50m/s