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Submitted on 1 Jan 1978

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THERMAL AND ELECTRICAL CONDUCTIVITY OF

PURE VANADIUM AT LOW TEMPERATURES

H. Weinstock, C. Tsai, F. Schmidt

To cite this version:

(2)

JOURNAL DE PHYSIQUE

Colloque C6, suppliment au no 8, Tome 39, aozit 1978, page

C6-1026

THERMAL AND ELECTRICAL CONDUCTIVITY OF PURE VANADIUM A T LOW TEMPERATURES

X H. Weinstock, C.L. T s a i and F.A. Schmidt

'

Department of Physics IZZinois I n s t i t u t e of TechnoZogy, Chicago, IL

60616 USA

R6sumd.- L ' a n a l y s e des mesures des c o n d u c t i v i t d s thermique e t d l e c t r i q u e de vanadium de h a u t e p u r e t d a rdv616 une n o t a b l e d i f f u s i o n Q l e c t r o n - d l e c t r o n 1 b a s s e s temp6ratures.

Abstract.- Measurements of b o t h t h e thermal and e l e c t r i c a l c o n d u c t i v i t y of h i g h p u r i t y vanadium have been analyzed t o show s i g n i f i c a n t e l e c t r o n - e l e c t r o n s c a t t e r i n g a t low temperatures.

INTRODUCTION.- E a r l i e r measurements by Jung e t a l , / l / on t h e thermal and e l e c t r i c a l c o n d u c t i v i t y of high p u r i t y vanadium have been extended t o below T f o r a sample w i t h p 3 001p4. 2 = 1760. This work i s aimed a t o b t a i n i n g a b e t t e r understanding of e l e c - t r o n s c a t t e r i n g mechanisms and t h e e l e c t r o n i c s t r u c - t u r e of vanadium. There a r e s e v e r a l important e l e c t r o n s c a t t e - r i n g mechanisms t o be considered / 2 / : electron-de- f e c t ; e l e c t r o n - e l e c t r o n ; electron-phonon i n t e r b a n d ; and electron-phonon i n t r a b a n d s c a t t e r i n g . For e l e c t r i c a l r e s i s t i v i t y , i f M a t t h i e s s e n ' s r u l e i s v a l i d , one may w r i t e 131 J (e/T) J S ( BIT) p = p,

+

p e e ~ 2 ,+ psdT3 7.212

'

'ssTS

m

'

(1)

e

where =

)'

dx i s t h e Debye i n t e - ( e % 1 2 0 g r a l . RESULTS.- E l e c t r i c a l r e s i s t i v i t y from 2 K t o 300 K shows a r e s i d u a l r e s i s t i v i t y of 10.9 &.cm and Tc

= 5.43 (f 0.02) K. F i g u r e 1 e x h i b i t s t h e thermal c o n d u c t i v i t y v s . temperature. The maximum v a l u e of thermal c o n d u c t i v i t y , 11.2 W/K.cm, o c c u r s a t about 8 . 0 K. Below T t h e thermal c o n d u c t i v i t y , i n t h e superconducting s t a t e , Ks, i s l e s s t h a n t h a t i n t h e normal s t a t e , Kn, w i t h (Kn

-

K ) i n c r e a s i n g a s T +

0, i n d i c a t i n g t h a t e l e c t r o n s a r e t h e dominant h e a t c a r r i e r s a t low temperature. Thus, i n t h e f o l l o w i n g

-

Ken, i . e . , a l l nor- a n a l y s i s , i t i s assumed t h a t K -

mal s t a t e thermal conduction i s due t o e l e c t r o n s . The measurements of b o t h thermal and e l e c t r i c a l con- d u c t i v i t y above 15 K a r e i n good agreement w i t h t h o s e of Jung, e t a 1 / l / , and show t h a t i n t r i n s i c e l e c t r o n i c t r a n s p o r t i s dominant i n t h i s range a l s o .

The b e s t f i t of eq. ( I ) t o t h e p(T) d a t a , f o r

The f i r s t term on t h e r i g h t hand s i d e of eq. ( l ) i s 0 = 380 K 171, i s

due t c e l e c t r o n - d e f e c t s c a t t e r i n g . The second term, p = (1.09 X 10-' + 1.30 X 10-'l T 2

+

2.75 x 10-l2

J J

P e e ~ 2 , was p r e d i c t e d by Appel / 4 / and observed f o r T3

3

+

9.50 x 10-16 T5 5 7.212 124.43) Q.cm. ( 3 )

s e v e r a l t r a n s i t i o n m e t a l s . The t h i r d term, suggested The b e s t f i t of t h e thermal d a t a , a p p l i e d t o by Mott 151 was v e r i f i e d e a r l i e r by White and Woods e a .

.

( 2 ) .

. .,

is

/3/ f o r vanadium. L a s t i s t h e

loch-Griineisen

term

-

=

a r i s i n g form i n t r a b a n d phonon s c a t t e r i n g of e l e c s Ken (0.446 + 1.30 X 1 0 - ~ T2

+

3.09 X 10-h T3)

t r o n s . c ~ . K ~ / w (4)

For thermal r e s i s t i v i t y , b o t h electron-pho-

ANALYSIS.- The Sommerfeld-Lorenz number e x t r a c t e d non i n t e r b a n d and i n t r a b a n d s c a t t e r i n g g i v e r i s e t o

from t h e s e measurements i s ' 2 . 4 4 X I 0-B (v/K)

',

q u i t e a q u a d r a t i c temperature dependence / 6 / . E l e c t r o n -

elwtron scattering yields a linear Thus, the c l o s e t o t h e accepted t h e o r e t i c a l v a l u e . The Lorenz t o t a l thermal r e s i s t i v i t y , m u l t i p l i e d by T, i s r a t i o o b t a i n e d f o r e l e c t r o n - e l e c t r o n s c a t t e r i n g ,

pee/B, i s 1.0 X ~ o - ' ( v / K ) ~ , c o n s i s t e n t w i t h e a r l i e r

- .

= A + B T ~ + c T ~

W T = - (2) experimental /8/ and t h e o r e t i c a l r e s u l t s / g / . The

en Ken v a l u e found f o r t h e e l e c t r o n - e l e c t r o n s c a t t e r i n g

'

Supported by t h e U. S. Department of Energy term i n e l e c t r i c a l r e s i s t i v i t y i s about 50 % h i g h e r

t

Address: Ames Laboratory

- DOE, Ames, Iowa,

USA than t h a t measured f o r niobium /2/. This can be a t -

t r s b u t e d t o t h e h i g h e r d e n s i t y of s t a t e s i n t h e d-

(3)

band of vanadium. The thermal resistivity due to

range reported here. Although electron-electron

electron-phonon interband scattering can be estima-

scattering appears unimportant for both thermal and

ted by

/3/

electrical resistivity at higher temperatures, such

- =

wsd(T)

2(:)2~3(~/~)

for T f 0.

scattering seems significant in determining both of

Wsd(">

these properties in the liquid helium temperature

with Wsd(m)

=

L ~ - ~ P ~ ~ T ~

J3(8/T)/J,(m)

=

1.24 cm.K/W.

range.

Thus, W T

=

1.12

X

C ~ . K ~ / W

and W

T = SS

1.97

X

::-*T3cm.K2/W.

Fig.

high

References

/I/ Jung, W.D., Schmidt, F.A. and Danielson, G.C.,

Phys. Rev.

B15

(1977) 650.

/2/ Webb, G.W., Phys. Rev.

181

(1969) 1127.

/3/ White, G.K. and Woods, S.B., Phil. Trans. Roy.

Soc.

(1959), 273.

/ 4 /

Appel, J., Phil. Mag.

8

(1963) 1071.

/5/ Mott, N.F., Proc. Roy. Soc. (London)

A153

(1935)

699.

161

Kemp, W.R.G., Klemens, P.G., Sreedhar, A.K. and

White, G.K., Proc. Phys. Soc.

A67

(1954) 728.

/ 7 /

Leupold, H.A., Iafrate, G.J., Rothwarf, F.

Breslin,

J.T., Edmiston, D. and Aucoin, T.R.,

J.

Low. Temp. Phys.

2

(1977) 241.

/S/ White, G.K. and Tanish, R.J., Phys. Rev. Lett.

19 (1967) 165.

/g/ Herring, C., Phys. Rev. Lett.

2

(1967) 167.

/10/ Parker, R.D. and Halloran, M.H., Phys. Rev.

(1974) 4130.

1 :

Thermal conductivity vs. temperature

purity vanadium.

for

W T can be estimated assuming a spherical Fermi

S S

surface, yielding a Fermi radius (k

)

of about

F

5.6

X

107 /cm. This value falls between those for

the experimentally determined hole surfaces of va-

nadium /10/ centered about

r

(7.1

X

10' /cm) and

centered about

N

(4.2

X

107/cm), assuming that the

geometries associated with these points lijcated in

the second and third Brillouin zones, respectively,

are transformed into spheres.

Consistency in the analysis of the data leads

to the conclusion that S-d or electron-phonon in-

terband scattering is dominant

in

determining the

value of electrical resistivity at low temperatures.

Both S-d and

S-S

(electron-phonon intraband) scat-

Références

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