Appendix D: List of Important Roman Symbols
637
(continued)
Symbol
Definition
m h
Effective hole mass
n
Index of refraction
N
Average number of electron-hole pairs
NA
Numerical aperture
n i
Intrinsic n-type carrier concentration
N ph
Photon density
n sp
Population inversion factor
P
Optical power
P 0 (x)
Probability distribution for a 0 pulse
P 1 (x)
Probability distribution for a 1 pulse
P amp,sat
Amplifier saturation power
P ASE
ASE noise power
P e
Probability of error
p i
Intrinsic p-type carrier concentration
P in
Incident optical power
P LO
Local oscillator optical power
P peak
Soliton peak power
PP x
Power penalty for impairment x
P ref
Reflected power
P sensitivity
Receiver sensitivity
P th
SBS threshold power
q
Electron charge = 1.60218 × 10 −19 C
Q
BER parameter
Q
Q factor of a grating
R
Bit rate or Data rate
R
Reflectivity or Fresnel reflection
r
Reflection coefficient
R
Responsivity
R APD
APD responsivity
R nr
Nonradiative recombination rate
R r
Radiative recombination rate
R sp
Spontaneous emission rate
S(λ)
Dispersion slope
T
Period of a wave
T
Absolute temperature
T 10–90
10-to-90% rise time
T b
Bit interval, Bit period, or Bit time
(continued)