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RFe3(BO3)4, R = Nd, Tb, Dy

01.04.11 -

-

- 2007


. ..

:

- , - ,

:

- , - ,

:

. ..

"15" 2007 . 16 . 501.001.02 . .. : 119992, -2, , , , , ______. . .. . "_____" 2007 . ..


1

. , 4f 3d , , , , , . , , , .. 4f-3d . . , , , . , : , , , f-d .. () RFe3(BO3)4, , . R = Gd, Nd [1, 2] , R . Fe N 30-40 . RFe3(BO3)4 ( R32)


2

, . , , . , , . RFe3(BO3) ,
4

, ,

,



(, ). , , , . . RFe3(BO3)4, , . : · , ; · , , ; · ,


3

; · . . : · , , ; · RFe3(BO3)4 R = Nd, Tb, Dy ; · , R = Tb, Dy R = Nd; - ; · ,



; · ; · ; · ; · .


4

-





.

. , . f-d , , . . : Moscow International Symposium on Magnetism (MSU, Moscow, 2005); " " (, 2005); XX - " " (, , 2006); III Joint European Magnetic Symposia (San Sebastian, Spain, 2006); 34 (--, 2006); XIII Feofilov symposium on spectroscopy of crystals doped by rare earth and transition metal ions (Irkutsk, 2007); I , " " (Multiferroics-2007) (--, 2007). . 15 , 1 1 . . . , , . 139 : - 41, - 2, 115 .


5

, . , . . ,

, RFe3(BO3)4 , . , ( R32) FeO6, . (N ~ 30-40 ) Fe3+ c . , , , . , f-d , . , ,
4







RFe3(BO3)

R.


6

, , . RFe3(BO3)4 i- (i =1, 2)



i

(R)

=

i CF

-g J B J i И B + fd M i Ы , К Ш
j = 1, 2, j № i.

(1) (2)
J

i ( Fe ) = -g S B Si И B + M j + fd mi Ы , К Ш
H
CF

­ , g

-

, J i - , gS = 2 ­ g-,
Si - Fe, fd < 0 < 0 -

R-Fe Fe-Fe . i- M i mi (1), (2) , , f-d [3], . , . , .

,


7

. d . , ,

, - . , , f-d . RFe3(BO3)4 R = Tb Dy. Fe , , . , M, mB/.. 10 T = 4.2 K 8 6 4 2 0 0 2 4 6 B, T 8 10 9.8 K 19 K 28 K TbFe3(BO3)4 B||c



. = 4.2 TbFe3(BO3)
4

~ 8

m/. ., DyFe3(BO3)

4

~ 6 m/. . . 1, TbFe3(BO3)
4

. 1. () () .


8

, - (- . 2). . 3 TbFe3(BO3)4 /T (T). B||c . c ( , ) c.
2.5 2.0 1.5 1.0 =0 0.5 M2 3 0 10 20 T, K 30 m1 40 0.0 0 = 3 T

B||c

M2 6 B , T 5

B M1 m1 m2

c B M1 m2

4

C/T, / K

7

2

10

20 30 T, K

40

50

. 2. B-T . , - (), .

. 3. TbFe3(BO3)4 / (). Tb , ­ .

"" () TbFe3(BO3)4. B^c . ,


9

, , . DyFe3(BO3)4, Dy3+ , Tb3+, . [4] .
a ,c

(T ) , -

, . 4. M a ( B ) ( 1), ,
a ,c

(T )

Dy3+ , 17 -1. , , ( 2), Dy3+ . Fe-Fe FeDy DyFe3(BO3)4: , (. 5) .. Dy , TbFe3(BO3)4


10
1.2

7

M, mB/..

6 5 4 3 2 1 0 0

c , mB/ ..

DyFe3(BO3)4
5 1 2 6

3 4

0.9 1

DyFe3(BO3)4
cc

B = 0.05

0.6 2

B^c
2 4 6 8 10 12 14

0.3

ca, b
0.0 0 50 100 150 200 250

B, T . 4. : 4.2 , D = 17 -1, (1) = 4.2 (2), 25 (3), 37 (5) 70 (6); b = 25 (4). ­ , ­ [4].

T, K . 5. . ­ [4], ­ . ­ c (1) a (2) .

B || c , . Dy3+, Tb3+, : , f-d , Tb3+, f-d . R = Nd, T < TN
30 - 32

, Fe , Nd , .
3+







(.

6)



Nd

c g- |g| » 2.65, |g| » 1.05,

, . , -


11


M, mB/. . 2.0 1.5 1.0 0.5 0.0 0

NdFe3(BO3)4 T=2K - B||a - B||c

4f

3



(. . 6). , ,

M, mB/. .

[7],

2.0 1.5 1.0 0.5 0.0 0

B||a

T=2K
2 4 6 8

, T

4 6 8 , T . 6. . ­ [5, 6], ­ [7], ­ . ­ , Nd Fe .

2

, b, (. 7). "" [5, 6]. , , , ~ 13 . (. 8), . ,


12

0.4 M, mB/. .
M2 m1

a m2 M1 B

c, mB/T . .

b

0.20 0.18 0.16 0.14

NdFe3(BO3)4 B = 0.1 T
cb

0.2

T=2K B||a NdFe3(BO3)
4

M, mB/. .

0.0 0.4

c, mB/T . .

ca

0.18 0.16 0 5 10

b B

cc
15 20 25 30

0.2

M2

m1

a m2 M1

T, K

T=2K B||b

0.0 0.0

0.3

0.6 0.9 B, T

1.2

. 8. . ­ 1.5 [5, 6], ­ .

. 7. . [5, 6], , ­ . ­ . Mi mi . , .



c



cb



, Nd3+. , Tb Dy,

, Fe . TN Nd3+, Tb3+ Dy3+.


13

4f-3d . , 4f-3d ­ RFe3(BO3)4 . , , , , .



, , . , [2], NdFe3(BO3)4 B || a , . 1 - . Nd
3+

(. 9) ,

Nd3+ f-d g-, .. . Tb
3+

-

TbFe3(BO3)4 , 10-3. , , l, - . Dy3+ DyFe3(BO3)
4

-


14

, , Tb.


(. 10)

, TbFe3(BO3)4 . DyFe3(BO3)4, ,

1
-3

NdFe3(BO3)4
c , 10 K
T= 4.5 K 6
-1 -4

8 TbFe3(BO3)4 6 4 2 0 8
-4

4

2 5

c

aa

, 10

mn

0 7 -4 4
1

3,4

c

x1x1

=c

x2x2

c

e1e1

=c

e2e2

T= 15 K

c , 10 K

6 4 2 0 0

c

-1

x1x1

=c

x2x2

DyFe3(BO3)4
c c
aa

0

mn

2 3

e1e1

=c

e2e2

-4 1

2

3

4

56 , T

7

8

9

50 100 150 200 250 300 T, K

. 9. - . 10. 3+ Nd ||a: 2 4 1 J O4 (1), J O4 (2), J 4 (3), TbFe3(BO3)4 1 2 0 J 2 (4), J O2 (5), J O2 (6) DyFe3(BO3)4 = 0.
3 J 4

(7 )

.

C , C , C



, < 50 , ,

.


15

DyFe3(BO3)4, TbFe3(BO3)4. ­ RFe3(BO3)4, R = Nd, Tb, Dy , . RFe3(BO3)4 R = Nd, Tb, Dy, . RFe3(BO3)4. B1 , B2 Bfd - , 1 , 2 fd ; fd - f-d ; ga gc - g- Nd3+ Dy3+ Tb3+. R Nd Tb Dy
1 ,

B

B1 ,

2 ,

B

B2 ,

fd ,

B

Bfd , 7.1 3.8 3.3

fd ,
-1

58 45 53

27 30 28

g

a

g

c

-3.87 -3.0 -3.53

-1.8 -2.0 -1.87

-0.47 -0.25 -0.22

8.8 [7] ~32 ~19

2.6 0.2 ~2

1.0 17.8 ~13

,



Fe-Fe



, . , , 1 , , , 2 , - , . ,


16

Tb

3+

Dy3+, Nd

3+



Bfd Fe . , , . , , , , R = Nd, Tb, Dy . 1. 2. , . - Fe , . 3. , a b . 4. :
c (T ) , ­ a (T ) b (T ) .

5.



. 6. , ,


17

. 7. . 8. - Fe . 9. , , . 1. Volkov D.V., Popova E.A., Kolmakova N.P., Demidov A.A., Tristan N., Skourski Yu., Buechner B., Gudim I.A., Bezmaternykh L.N. Magnetic properties of TbFe3(BO3)4//JMMM. - 2007. -V. 316. - P. e717-e720. 2. Popova E.A., Volkov D.V., Vasiliev A.N., Demidov A.A., Kolmakova N.P., Gudim I.A., Bezmaternykh L.N., Tristan N., Skourski Yu., Buechner B., Hess C., Klingeler R. Magnetization and specific heat of TbFe3(BO3)4: Experiment and crystal-field calculations//Phys. Rev. B. - 2007. - V. 75. ­ N. 22. - P. 224413-224422. 3. .., .., .. NdFe3(BO3)
4

//. - 2007. - T. 131. - 6. - C. 1030-1040.


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4. Demidov A.A., Kolmakova N.P., Takunov L.V., Volkov D.V. Magnetoelastic effects in the trigonal 4f­3d crystals: RFe3(BO3)4//Physica B. 2007. - V. 398. - P. 78-84. 5. .., .., .., .. RFe3(BO3)4, R = Nd, Tb, Dy, Er// . ­ ( ). 6. Demidov A.A., Kolmakova N.P., Popova E.A., Vasiliev A.N., Volkov D.V. What orientation of iron magnetic moments are stabilized by various rare earths in the ferroborates RFe3(BO3)4//Abstracts of Moscow International Symposium on Magnetism, Moscow, Russia, 2005. - . 668. 7. .., .., .., .., .. RFe3(BO3)4 // " ", , 2005. - C. 25. 8. Volkov D.V., Popova E.A., Kolmakova N.P., Demidov A.A., Tristan N., Skourski Yu., Buechner B., Gudim I.A., Bezmaternykh L.N. Magnetic properties of TbFe3(BO3)4//Abstracts of III Joint European Magnetic Symposia. Spain, San Sebastian, 2006. - P. 68. 9. .., .., .., .., .., ., .. - TbFe3(BO3)4// XX " " (-20), 2006. ­ . 591-593. 10. .., .., .. RFe3(BO3)4// 34


-34. --, 2006.T. 1.-C. 183.


19

11.

.., .., .., ..,


.., ., .. TbFe3(BO3)4// 34 T. 1. -C. 78-79. 12. ..,


-34. --, 2006. .., ..









TbFe3(BO3)4// 34 13. Nd
3+

-34.

--, 2006. - T. 1. - C. 115-116. Demidov A.A., Kolmakova N.P., Volkov D.V. Influence of the ground multiplet structure on magnetic properties of NdFe3(BO3)4//Abstr.

of XIII Feofilov symposium on spectroscopy of crystals doped by rare earth and transition metal ions. Irkutsk, Russia, 2007. ­ P. 28. 14. Volkov D.V., Demidov A.A., Kolmakova N.P., Takunov L.V. Crystal-field effects in the rare-earth ferroborates RFe3(BO3)4, R = Nd, Tb, Dy, Er//Abstr. of XIII Feofilov symposium on spectroscopy of crystals doped by rare earth and transition metal ions. Irkutsk, Russia, 2007. - P. 144. 15. .., .., .., .. RFe3(BO3)4, R=Nd, Tb, Dy// I " " (Multiferroics-2007). -, 2007. - C. 63-66. 16. .., .., .. " NdFe3(BO3)4// I " (Multiferroics-2007). -, 2007. - C. 111-115.


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1. .. , .. , .. ., 81, 335 (2005). 2. .. , .. , .. ., 86, 600 (2006). 3. .. , .. , .. , .. , , , (1985), 296 c. 4. .. . 5. .. , . .. , . 34- , .1, (--, 2006), . , -- (2006), . 32-33. 6. .. , . , X. ., 132, 121 (2007). 7. M.N. Popova, E.P. Chukalina, T.N. Stanislavchuk et al., Phys. Rev. B 75, 224435 (2007).