HIGH-Q OPTICAL FIBER FILTER FOR QUANTUM KEY DISTRIBUTION SYSTEMS

SKU0007
DESCRIPTION

High-Q fiber-optic filters are designed to reflect or transmit optical radiation with delay in fiber-optic communication lines. These devices provide high precision in wavelength selection, excellent reflectivity, reliability, and long service life. The filters are produced using advanced technologies. The core structure consists of periodic refractive index modulation structures, induced in the core of optical fibers, known as fiber Bragg gratings, as well as various specialized structures based on them. Additionally, methods such as lithographic etching of silicon substrates and other techniques are used to create filters outside the internal structure of the fiber. The presented fiber-optic filters possess the best characteristics and high reliability. A scientific and technological laboratory setup has been developed for creating Bragg gratings in optical fibers with the necessary parameters, enabling the production of fiber-optic spectral filters for quantum communication lines.

ADVANTAGES OF THE DEVELOPMENT

  • Narrow spectral line, up to 50 pm at half-height at 1550 nm wavelength
  • Ability to adjust the resonance wavelength of the fiber filter
  • The setup allows tuning the Bragg resonance wavelength (BWR) over a wide range
  • The use of a laser beam up to 50 mm in length to create the interference pattern
  • Small (about 250 µm) diameter of optical fiber
  • Low weight of the optical fiber
  • Versatility of the form factor and ease of mounting the optical fiber
  • Inductance-free design

CHARACTERISTICS

  • Spectral width of the central maximum reflection at -2 dB (D): no more than 0.08 nm (BFOF type 2)
  • Spectral width of the central maximum reflection at -25 dB (D): no less than 0.03 nm (BFOF type 2)
  • Wavelength tuning range (with step no more than 1 GHz) of the central wavelength of the BFOF: at least ± 20 GHz
  • Reflection coefficient at the reflection peak: no less than 80% (BFOF type 1.3), no less than 99.9% (BFOF type 4)
  • Working wavelength range: 1000–1750 nm
  • Time to reach operating mode: no more than 10 minutes
  • DC power supply voltage: 5 ± 0.5 V
  • Maximum power consumption: no more than 5 W
  • Service life: 5 years
  • Maximum attenuation at the central minimum transmission: no less than 41 dB (BFOF type 2)
  • Dimensions of BFOF (W×D×H) for all types: (54×165×20) ± 2 mm

APPLICATION AREAS

  • Communication systems for signal filtering
  • Systems with high-power laser radiation to eliminate scattering signal combinations
  • As part of multiplexing and demultiplexing devices
  • In quantum key distribution systems
  • In fiber laser resonators
  • In physical quantity sensors