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HAL Id: jpa-00246965

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Note on ultrasonic effects due to third-order elastic coefficients in icosahedrally symmetric systems

Shmuel Goshen, Joseph Birman

To cite this version:

Shmuel Goshen, Joseph Birman. Note on ultrasonic effects due to third-order elastic coefficients in icosahedrally symmetric systems. Journal de Physique I, EDP Sciences, 1994, 4 (7), pp.1077-1084.

�10.1051/jp1:1994185�. �jpa-00246965�

(2)

Classification

Physics

Absn.acts

43.25 61.50E 62.65

Note

on

ultrasonic effects due to third.order elastic coefficients in icosahedrally symmetric systems

Shmuel Y. Goshen

(1)

and

Joseph

L. Birman

(2)

(') Physics Dept.,

Nuclear Research Center, Negev, P-O- Box 9001, Beer-Sheva 84190, Israel (2)

Physics Dept.,

City

College

of the

City

University of New York, New York, NY10031,

U-S-A-

(Received 6

September

J993, ievised14 Maiih 1994, accepted 2/ Maic.h 1994)

Abstract. The identification of

alloy

systems of Almn and other compounds with macroscopic icosahedral symmetry bas been reported. In this work we discuss several

macroscopic

tensor

properties

which may

distinguish

between icosahedral

point

group symmetry I, from either fuit isotropic SO (3) symmetry, or cubic O symmetry.

Emphasis

is given to trie structure of trie third order elastic coefficient tensor and the non-linear elastic coefficients which anse

in I-symmetry systems.

Corresponding

sound velocities are obtained these can permit

experimental

measure-

ments using ultrasonic

techniques.

One of the very

interesting

recent

developments

m condensed matter

physics

has been the

discovery

and

synthesis

of a

variety

of cristalline systems whose symmetry is

non-crystallogra- phic.

That is neither the

point

group symmetry nor the space group symmetry are among the

32,

or 230

(respectively)

groups of 3-dimensional

crystallography.

The first of these new discovenes to our

knowledge

was the

synthesis

of an Al-Mn

alloy

with

stoichiometry approximately Al~mn by

Shechtman et ai.

il ]. They

carned out electron- diffraction studies which demonstrated that the pattem of scattered electrons

possessed

icosahedral symmetry. In

addition, algorithms

have been

developed

for

mdexing

of the

locations of observed diffraction spots, consistent with the

predictions

of

quasipenodic

translational order.

Quite recently, large perfect samples

of

quasicrystals

have been available owmg to new

developments

in material

preparation.

This has

permitted

the first observation of

dynamical

X- ray diffraction effects as earlier

predicted [2],

on a

quasicrystal

of « f-c-c- » Al-Pd-Mn,

including

the observation of the Borrmann

effect,

or « anomalous transmission at the

Bragg angle

»

[3]. Samples

on which the expenments were

performed

were of centimeter size. With such

samples available,

it can be

possible

to determine novel

macroscopic

properties of these

icosahedral materais.

In this note we restnct attention to some of the novel

physical,

measurable macroscopic

consequences of icosahedral

point

symmetry. To

phrase

the

problem

more

exactly

we ask what type and order of tensonal response coefficient can be used to charactenze the presence

JOURNAL DE PHYSIQUE -T 4 N' 7 JULY J994 ~9

(3)

1078 JOURNAL DE PHYSIQUE I N° 7

of icosahedral symmetry, and

distinguish

from

isotropic (complete

SO

(3)),

or cubic

(point

group

O) symmetries

? We suppose a

single crystal

of suitable size is

available,

and can be

aligned

so that suitable

polarized

measurements can be made.

As a first step we recall

[4]

that the components of the

physical

response functions for

crystal

systems can be classified as cartesian tensors, the indices of which possess some

permutational symmetries.

These tensors are reducible into a sum of irreducible components. Thus in an

isotropic

SO

(3)

system the response functions transform as a sum of

sphencal harmonics,

and the irreducible representations are

conventionally

denoted

D~~'.

In the presence of G point group

symmetry

the bases of each

representation

D~~~

splits

into irreducible

representations

of G

D~~~

= D~~ e D~"~ e

where D~'~,

D~'~

are irreducible

representations

of G. Then

by

measunng the components associated with different irreducible

representations #1',

effects which are

specific

to the lower («

spht »)

symmetry can be identified. The number of

physical

parameters is determined

by

the number of times that the

identity representation

appears.

Applymg

this to our case, m table I we grue the standard character table of the icosahedral group I and the

compatibility

(or

splittings)

table of the representations

D'~~

under I. From this table, and the earlier work

by Ripamonti [5]

we can find a vanety of «

higher

order

» tensonal

properties

which may be used to differentiate between

O,

I, and SO

(3).

These are given in

table II.

Table I.

a)

Chaiac.tel table

defining

the

iii educible representations

of

the icosaheclial point groiip I.

b) Compatibility

table

foi-

ieduction

of

D~~~

of

SO

(3),

iestricted to point gioiip I.

a)

E 15

C~

20 C~ 12 C~ 12

Cl

A

~ ~ ~

+ ,

,<'5

' ~

2 ~ 2

~ ~ j ~

,,1- ,/j

+

~ ~

2 ~ 2

G 4 0

H 5 0 0

b) Do

=A

Dj =F,

D~

=

H D~

=F~+G

D~

=G+H

D~

=Fi+F~+H

D~ =A+Fj+G+H

An interesting and

practical

case is of nonhnear elastic wave

propagation

where the third order elastic

(TOE)

coefficients are used. For the icosahedral

symmetry

there are four

(4)

Table II.

Highei

oider tensoi

piopeities (see Ref [2]).

Physical

property, Number of parameters

Physical

property

representing

relation

between : Isotr. I

Symmetric

tensor and 3 4 6 56 Third order elastic

square of

symmetric

coefficients

tensor

subject

also to Maxwell relation

Symmetric

tensor and 4 5 9 126 Second order

photo-

square of

symmetric

elastic coefficients

tensor

Second rank

symmetric

2 3 6 90 Second order resis-

tensor and a

totally

tance second order

symmetric

fourth rank

magnetothermal

con-

tensor

ductivity

Second rank

general

2 3 7 135 Second order magneto-

tensor and a

totally

electric power

symmetric

fourth rank tensor

Second rank

symmetric

5 6 12 216

Piezomagneto-

tensor and a fourth resistance

rank tensor

symmetric

inside the first

pair

and the second

pair

parameters, while for the

isotropic

case there are three. For the second order elastic coefficients of the linear elastic wave

propagation

both

symmetries,

the isotropic and icosahedral have

only

two parameters. The 2 +4 = 6 parameters of materais of icosahedral symmetry can be

jnvestigated by

ultrasonics. Five of the parameters are the same as t'or

isotropic

symmetry.

How

significantly

the sixth parameter differs from zero will grue the

special

properties related

to the icosahedral symmetry.

By

these

investigations

it is

impossible

to decide about the existence of a center of symmetry because

they

are based on second order tensors. Nonlinear effects in elastic wave

propagation

may anse from several different causes. We shall discuss and calculate the

following

two

cases. First, the

amplitude

of the elastic wave may be

sufficiently large

so that finite strams

anse. An

initially

sinusoidal

longitudinal

wave of a given

frequency

distorts as it propagates,

and energy is transferred from the fundamental to the harmonics. The amount of energy

transferred

depends

on the TOE coefficients and is a way of

experimentally determmmg

them.

Second, a materai which in its undeformed state behaves m a lmear fashion may behave in a

nonhnear fashion when mfinitesimal ultrasonic waves are

propagated, provided

that a

sufficient amount of externat static stress is

imposed. Usually

this is in the form of uniaxial or

hydrostatic

compression. The formulas for the velocities for

longitudinal

and transverse

(5)

1080 JOURNAL DE PHYSIQUE I N° 7

modes, in the different directions under different extemal stresses

permits

the

experimental

determination of TOE coefficients. We use the well-established notation of Green

[6].

The

Lagrangian

symmetric strain matrix y is

given by Mumaghan [7]

as

y =

(ÀJ à) (1)

where J is the Jacobian matrix :

ôXj

J~t

w

(2)

ôat

Here a,

(1=1, 2, 3)

are the cartesian coordinates of a point in the unstrained

solid, X,

(1 = 1, 2,

3)

are the coordinates at time t of the point in the deformed solid, and à is the unit

matrix.

The

engineering

stress tensor

(which

is not

symmetnc)

is defined

by

T=J~ (3)

Y

where

#

is the strain energy, and its form is

specified by

the symmetry of the solid. The equations of motion in the

Lagrangian

coordinates for the deformations

u~ are

ôT~~

$

~ P° ~i

~~l

j J

where u, =

X,

a, (1

= 1, 2, 3 ), po the undeformed

density,

and ü is

Î~

~ in the

Lagrangian

formulation.

Now

wnting

for the strain energy çS, when the z axis has a 5-fold symmetry, and the y-axis is

of a ?-fold symmetry

~ ÀL

(Y22

Y33 Y23 Y32 + Y33 TII Y13 Y31 + TII Y22 Y12

Y21)

+

+ ~~ ~

~'~~

(Yjj

+ Y?? + Y33)~

3

2

m(yjj

+ y~~ +

y33)(Y22

Y33 Y23 Y32 + Y33 Yl1 Y13 Y31 + Yj Y22 Y12 Y2j +

+

n(yj

y~2 Y33 Y11 Y23 Y32 Y21 Y12 Y31+ Y21 Y13 Y32 + Yii Y12 Y23 Y31 Yii

Y22)

+

~[YÎ3

+

(TII

+

YÎ2)

Y33

YÎ3(Yll

+

Y22)

+ 2 TII Y22 Y33

+ ~ Y13 Y31 TII + ~ Y23 Y32 Y22 ~ Y13 Y31 Y3~ ~ Y23 Y32 Y33

+

(Y13

+

Y31)(Yll

Y22)~ +

~(Y22 Yll)(Y12

Y23 + Y32

Y21)

~ Y12 Y21

(Yl~

+ Y~l + 4 Y12 Y23 Y31 + ~ Y13 Y~2 Y211

(5)

The five terms whose coefficients are (2 M +

),

M, f + 2 m, m and n,

respectively,

are

isotropic. The calculation of these terms is descnbed in Green

[6].

The last term, which is anisotropic but has

only

icosahedral symmetry, was calculated

by

Butler's tables. We shall also need the expression for çS when the z axis has a 3-fold symmetry and the y axis has a 2-fold

(6)

symmetry. Then this last term becomes

~

ÎÎ °'~' /7

°'~~

°'~'

°'~~

~°'~'

~ °'~~~ °'~~ ~ °'~~ °" ' ~ +

j YÎ3(Yll

+

Y22)

+

)

TII Y22 Y33 + Y12

Y21(~

Y22 ~ TII

Y31)

+ Yl~

Y31(~

Y3~ ~ TII ~

Y22)

+ Y23

Y32(~

Y33 Y22 ~ TII +

(Y12

Y23 Y31 + Yl~ Y32

Y21)

/j

+

'j (Y13

+

Y31)(5 YÎI

~

YÎ2

~ Y11 Y22 ~ Yl1 Y3~ + 8 y22 y~3

~ Y12 Y21 + 16 Y23 Y32

~/

Y13 Y31 +

+'~~ (yj7

y71+ y17 y7j

)(16

vii 4 yjj 12

~~)j

(6)

9

First case.

Harmonic distortion of a finite

amplitude

harmonic wave. For a pure

Longitudinal

ultrasonic

wave we get

Po =

(2

» + À

)(u,,u fia,,11,,,,) (7a)

p

is the

nonlineanty [6] parameter

:

P

=

3

+

~~Îi/ i

i~~~ (7b)

Here :

K

=

3 g in the direction of 5-fold axis K

=

0 in the direction of 2-fold axis

(7c)

K

=

~

g in the direction of 3-fold axis 9

The solution up to the second harmonic

[6]

r (a, t =

Ai

sin

(ka

wt + A7 cos 2

(ka

mi

(8a)

Ai

is the fundamental wave

amplitude.

A~,

the

amplitude

of the

generated

second harmonic

A~ =

j (A)

k2 ap

). (8b)

Therefore,

the

discontinuity

distance

[6]

is :

~

p

2

po(~f)~

ii~ ~~~~

where w

=

?

~f

and uo is the

amplitude

of the wave at a 0.

Second case.

Measurement of the variation of ultrasonic wave

velocity

with

applied

externat stress.

(7)

1082 JOURNAL DE PHYSIQUE I N° 7

Let us define

[6]

:

il : the wave

velocity,

pjj the unstrained

density,

P an

imposed

externat

hydrostatic

pressure,

T an

imposed

externat uniaxial stress in a

specified

direction.

We get the

following

equations for the

velocity,

V, of the waves in the directions of symmetry, with constraints indicated

Extemal

hydrostatic

pressure

longitudinal

wave

along

ail symmetry directions.

poil~= (2p

+À)- ~

(7À +10p +6i+4m +2g). (9)

3À +2 p

II. Externat

hydro~tatic

pressure ;

transverse wave

along

ail symmetry directions.

pov~=p-

~

[6p

+3À +3m-

~nj (10)

(3À +2p) 2

III. Externat compressive stress

along

5-fold axis ;

longitudinal

wave I stress.

p~V~=(2p+À)-~~~~~ ~(~~~(4À+10p+4m+6g)+~~~+À+2ij,

+-R R R

(11)

IV. Externat compressive stress

along

2-fold axis

longitudinal

wave

along

5-fold axis 1 stress.

Po~'~= ~2/l+À)~~~ l~~~12f-~/

(m+À

+2JL)l~(2À +JL)1. ('2)

V. Externat

compressive

stress

along

3-fold axis

longitudinal

wave I stress,

v~~?/~+~~-~~iili~jil~io~+~m~+~+2fH~'2~+~/~~'.

"~~

VI. Externat compressive stress

along

2-fold axis

longitudinal

wave

along

3-fold axis 1stress.

T

[~(_~~(m+À+2Rl+@~~~~~~~Î

~~~~

p~~i'2=(2p+À)-~~~

+2p)

R

(8)

VII. Externat

compressive

stress

along

5-fold axi~

longitudinal

wave

along

2-fold axis 1 stress,

p~V~= (2p

+À)- ~

[2i-~~ (m+À +2p~+~~~ ~~~gj (15)

(3À +2p)

p R

VIII. Externat

compressive

stress

along

2-fold axis

longitudinal

wave I stress.

p~V~= (2p +À)-

~

[~

~~

(4À

+10p

+4m)-~~

+2ij. (16)

(3À +2p)

p p

IX. Extemal

compressive

stress

along

5-fold axis

transverse wave I stress with

particle displacements along

?-fold axis.

p~V~=p-

~

~

[m+4p+4À +£-~~~~~~~~j. (17)

À

+2p)

p p

X. Externat

compressive

stress

along

2-fold axis

transverse wave

along

5-fold axis 1 stress with

particle displacements

I ~tress.

p~v2=

~_

T

[~~~

~ ~

(3À+2p)

~~~~~/~)

~ ~~

4p~

p

~' ~~~~

XI. Externat compressive stress

along

?-fold axis ;

transverse wave

along

5-fold axis 1 stress with

particle displacements

1 stres~.

p~

V~

= p

~

~

m

2 ~~ ~ ~ ~~

(

+2p) 2p

(19)

In conclusion we have

presented

results which can be used in the determination of the icosahedral component of macroscopic elastic response of a

quasicrystal.

Ii would be of considerable interest to have such measurements made on the new,

large-size

materais, in order to check these results, and aise with an atm of

relating

to

microscopic

theories of

elasticity

of

quasicrystals recently proposed [9].

A recent

expenmental

review of the

physical

properties of

quasicrystals (10] heightens

interest in the measurement of macroscopic properties of these systems. A

noteworthy

related

work

by

Amant, de Boissieu and Zarembowich

[1Ii

measures elastic properties

ultrasonically

under

hydrostatic

pressure. No anisotropy was found and

they reported

measurement of

only

two

independent

linear combinations of the four TOE coefficients (see here

Eqs. (9, 10)

and Tab. I in

[1Ii).

Acknowledgments.

We thank Prof. F. Fumi, and a referee for

pointing

Dut the relevant work of reference [5

].

One of us (JLB) thanks Prof. A.Goldman for

sending

the

preprint, reference[3(,

before

publication,

aise Prof. R. Colleta for discussions of

possible Dynamical

Diffraction exper-

iments which can be carned Dut on the

large quasicrystals,

and Prof. A. Zarembowitch and

Dr. B. Perrin for discussions of their recent work

[1Ii

The work was

supported

in part

by

a

PSC-FRAP-CUNY grant.

(9)

1084 JOURNAL DE PHYSIQUE I 7

References

il Schectman D., Blech I.. Grattas D. and Cahn J. W.,

Ffij,s.

Roi. Len 53 (1985~ 195 A review is given in Gratias D.. Cfimenip Ffiys. 28 <1987) 219.

[2] Berenson R. and Birman J. L., Ffiy.i. Roi>. B 34 <1986~ 8926.

[3] Kycia S. W., Goldman A. I., Lograsso T. A., Delaney D. W.. Black D., Sutton M., Dufresne E..

Bruning R., Rodencks B., Fhj~s. Rei>. B 48 <1993) 3544.

[4] Bhagavantam S., Crystal Structure and Physical Properties <Academic Pre~~. London-New York, 1966).

[5]

Ripamonti

C.. J. Ffi_i~5. Fiaiic.e 48 <1987) 493.

[6] Green R. E. Jr.. Ultrmonic

Investigation

of Mechanical

Properties

<Academic Pre~~. New York- London, 197~j wherein Table gives the relations between the different notations

Breazeale M. A. and Philip J., p. in Fhi>sic.a/ Acoi<.çiic..ç <edited by W. P. Mason and R. N.

Thurston), Vol. XVII (Academic Pres~, New York, 1984) ; Breazeale M. A. and Ford J.. J App/. Fhys. 36 <1965~ 3486.

[7] Murnaghan F. D., Finite Deformation of an Ela~tic Solid

(Wiley.

New York, 1951 Dover, New York, 1967~.

[8] Butler

Philip

Il., Point

Group Symmetry

Application~ <Plenum Press, New York-London, 1981) [91 Bak P., Ffiv.i Rei B 32 (1985) 5764 :

also ~ee

Quasicrystal;,

Theory and Experiment (Vols. 1-3) M. V. Jaric Ed. <Acaclemic Press, 1989- 90).

loi Jeong H. C. and Stemhardt P. J., A New Approach to Quasicrystal~ <prepnnt U. of Penn, 1994).

[1Ii Takeuchi S..

Phy~ical

Properties of Quasicrystal~. An Expenmental Review, in

Quamcrystal~

anal

Imperfectly

Ordered

Crystals

(Tran~. Tech. Pub., 1994),

Proceedings

of an International

Symposium

in

Chengde,

China (August 1993).

See especially Amazit Y.. de Boissieu M.. Zarembowitch A.. Eurfipfi_1,sic.i Len. 20 (1992) 703 Amazit Y., Fischer M.. Perrin B., Zarembowitch A., de Boissieu M., ibid. 2511994) 441.

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