Lithium Niobate

Material
LiNbO3

 

Lithium Niobate (LiNbO3) possesses a combination of unique electro-optical, acoustic, piezoelectric, photoelastic and non-linear optical properties with exhibiting mechanical and chemical stability.

 

Lithium Niobate is strongly birefringent, lacks inversion symmetry and displays Pockels effect. Its birefringence is highly temperature dependent. That's why accurate heating of the crystal can be used to achieve phase matching in the medium. It possesses large effective non-linear, electro-optic and acousto-optic coefficients.

 

Lithium Niobate is commonly used in electro-optical, acousto-optical and non-linear optical devices, Pockels cells, optical parametric oscillators (OPO), optical switches for gigahertz frequencies, high-temperature acoustic transducers, receivers and transmitters of acoustic vibrations, laser frequency doubling, Q-switching devices for lasers.

 

The transverse modulation is mostly employed for lithium niobate crystals for using as frequency doubler for wavelength >1µm and OPO pumped at 1064nm as well as quasi-phase-matched frequency doublers.

Properties
Optical properties
Transmission range
320 ‐ 5600
Refractive index @1300 nm
ne=2,146

no=2,220

Reflection losses in % at 1 surface @ 633 nm
14,6
optical homogeneity in 1/cm
5·10-5
NLO coefficients in pm/V
d33= 34,40

d31=d15= 5,95

d22= 3,07

Damage threshold in MW/cm2 (10ns)
200
Absorption loss in %/cm @1064 nm
< 0,1
Physical properties
Density in g/cm3
4,64
Melting point in °C
1253
Specific heat capacity in J/(kg · K)
628
Thermal conductivity in W/(m · K) @25°C
4,19 (⊥ c-axis)

4,6 (∥ c-axis)

Thermal expansion in 1/K @25°C
14,8 · 10-6 (⊥ c-axis)

4,1 · 10-6 (∥ c-axis)

Dielectric constant @298K, 100kH
82
Solubility in water in g/100g
insoluble
Mohs hardness
5
Knoop hardness in kg/mm²
630
Material type
single crystalline, synthetic
Crystal structure
hexagonal
Lattice constants in Å
a = 5,15

c = 13,86

Elastic coefficient in GPa
C11 = 202

C12 = 55

C13 = 71

C14 = 8,3

C33 = 242

C44 = 60,1

Young's Modulus (E) in Gpa
170
Shear Modulus (G) in GPa
68
Bulk Modulus (K) in GPa
112
Poisson's ratio
0,25
Spectral properties
sample thickness: 1,7 mm