High backscattering waveguides
A high backscattering fiber comprising a perturbed segment in which the perturbed segment reflects a relative power that is more than three (3) decibels (dB) above Rayleigh scattering. The high backscattering fiber also exhibits a coupling loss of less than 0.5 dB.
1. An optical fiber having a modified refractive index caused by applying a spatial pattern that creates a refractive index perturbation, the optical fiber comprising:
an effective index of n eff ;
a numerical aperture of NA;
a scatter of R p→r (fiber) ;
a total transmission loss of α fiber ;
an in-band range greater than 1 nm; and
a figure of merit (FOM) in the in-band range, FOM>1, the FOM being defined as:
F
O
M
=
R
p
→
r
(
fiber
)
α
fiber
(
NA
2
n
eff
)
2
.
2. The optical fiber of claim 1 , the in-band range being between approximately 1450 nm and approximately 1650 nm.
3. The optical fiber of claim 2 , further comprising:
a coupling loss less than 0.2 dB in the in-band range when coupled to a G.652-standard compliant optical fiber.
4. The optical fiber of claim 2 , further comprising:
a total backscatter greater than −99 dB/mm within the in-band range; and
a transmission loss less than 2 dB/km within the in-band range.
5. The optical fiber of claim 2 , further comprising:
a total backscatter greater than −99 dB/mm within the in-band range; and
a transmission loss less than 10 dB/km within the in-band range.
6. The optical fiber of claim 4 , further comprising:
a coupling loss less than 0.2 dB in the in-band range when coupled to a G.652-standard compliant optical fiber.
7. The optical fiber of claim 1 , further comprising a length that is greater than 20 cm.
8. The optical fiber of claim 1 , the FOM being greater than 2.
9. The optical fiber of claim 1 , further comprising:
an out-of-band range; and
an optical pump having a wavelength in the out-of-band range.
10. A high backscattering optical fiber having a modified refractive index caused by applying a spatial pattern that creates a refractive index perturbation, the high backscattering fiber comprising:
an operating wavelength range;
a total backscatter greater than −99 dB/mm within the operating wavelength range; and
a transmission loss less than 2 dB/km within the operating wavelength range.
11. The high backscattering fiber of claim 10 , further comprising:
a bandwidth (Δλ), wherein Δλ≧1 nm;
an in-band reflectivity enhancement factor (γ in-band ), wherein γ in-band ≧10 dB; and
an out-of-band reflectivity suppression factor (δ out-of-band ), wherein δ out-of-band ≧2 dB.