GaAsSb - Gallium Arsenide Antimonide

Mechanical properties, elastic constants, lattice vibrations

Basic Parameter
Elastic constants
Acoustic Wave Speeds
Phonon frequencies

Basic Parameter

Bulk modulus (7.53-1.9x)·1011 dyn cm-2
Density 5.32 + 0.29x g·cm-3
Hardness on the Mohs scale between 4 and 5
Surface microhardness
(using Knoop's pyramid test)		 750 kg mm-2 for x=0 (GaAs)
450 kg mm-2 for x=1 (GaSb)
Piezoelectric constant e14=-(0.16 - 0.03x) C m-2
Cleavage plane {110}

Elastic constants 300 K.

      C11=(11.9 - 3.07x)·1011 dyn/cm2
      C12=(5.34 - 1.32x)·1011 dyn/cm2
      C44=(5.96 - 1.64x)·1011 dyn/cm2

For T = 300 K

Bulk modulus (compressibility-1) Bs= (7.53 - 1.9x)·1011dyn/cm2
Anizotropy factor A=0.55
Shear modulus C'=(3.28 - 0.88x)·1011dyn/cm2
[100] Young's modulus Yo= (8.59 - 2.28x)·1011dyn/cm2
[100] Poisson ratio σo = 0.31

Acoustic Wave Speeds

Wave
propagation
Direction		 Wave
character		 Expression for wave speed Wave speed
(in units of
105 cm/s)
[110] Vl [(C11+Cl2+2C44)/2ρ ]1/2 5.24 - 0.86x
Vt|| Vt||=VT=(C44/ρ)1/2 3.35 - 0.58x
Vt⊥ [(C11-C12)/2ρ]1/2 2.48 - 0.41x
[111] Vl' [(C11+2C12+4C44)/3ρ]1/2 5.40 - 0.90x
Vt' [(C11-C12+C44)/3ρ]1/2 2.80 - 0.47x

Phonon frequencies

Optical phonon energy as a function of x.
Full and open circles show TO phonon frequencies
(Lucovsky and Chen (1970)).
Crosses show LO phonon frequencies
(Filion and Fortin ( 1974)).