Common
Symbol
|
Meaning
|
c
|
speed of light (c = 299,792,458 m/s approx 3 x 106m/s)
|
ν
|
frequency
|
h
|
planck's constant (h = 6.62606896x 10-34 J s = 4.135667 x 10-15eV s)
|
λ
|
wavelength (visible spectrum is 400-700nm)
|
Absorption and Emission
Symbol
|
Meaning
|
ε
|
extinction coefficient of a molecule
|
Φ
|
quantum yield
|
Ψ
|
wave function
|
EO Properties
Symbol
|
Meaning
|
μ
|
dipole moment (mu) measured in debyes
|
α
|
linear polarizability (alpha)
|
β
|
first order hyperpolarizability (microscopic) (beta)
|
cos3θ
|
order parameter
|
δ
|
Two photo cross section measured in Goppert-Mayer units (GM), with 1 GM=1×10-50 cm4 s molecules−1 photon−1 >100gm is high.)
|
r
|
Pockels coefficient or Linear Electo-optic Cofficient Pockels Effect r~ 10-12 – 1—10 m/V
|
r33
|
Electro-optic cofficient (chi 33)(FM= 1000 pm/V)
|
χ2
|
second-order nonlinear susceptiblity (first order hyperpolarizability) (macroscopic)
|
χ3
|
third-order nonlinear susceptiblity (second order hyperpolarizability) (macroscopic) (alpha)(FM= 6-7 x 10-21(m/V)2)
|
ε
|
dielectric constant or relative static permittivity
|
M
|
Transition dipole moment (measured in debyes)
|
N
|
Number Density parameter
|
φfl
|
Fluoresence Quantum Yield a ratio of photons absorbed over photons emitted
|
σ
|
conductivity (measured in S (Siemens)/cm
|
t
|
the electronic coupling, transfer integral or resonance integral
|
vπ
|
half-wave driving voltage
|
Devices
Symbol
|
Meaning
|
α
|
material loss in dB/cm
|
d
|
electrode separation
|
Γ
|
optical electrical overlap
|
λ
|
reorganization energy
|
μ
|
charge mobility in cm2 / V s- a mobility >1 is considered good
|
see also Wikipedia Greek Letters in Science