Single-mode optical fibres. Raman gain efficiency measurement using continuous wave method. Guidance

A novel high speed and ultra long-haul radio-over-fiber (ROF) system based on Dual Photoelectric Arms Coherent Modulation (DPACM) and Optical Duo-Binary Coding (ODBC) is proposed, and demonstrated. The signal spectrum bandwidth, generated by ODBC based on the first order DPACM, is half of non-return-to-zero (NRZ ) signal spectrum bandwidth. The secondary order DPACM generates a 40-GHz Millimeter-wave (mm-wave) that is transmitted over fiber (ROF). The simulation results show that, the bit rate can be up to 40 Gbps and the transmission distance is over 1500 Km, based on the ROF system with a 0 dBm continuous-wave laser source, multiple stages Er-Doped Fiber Amplifier (EDFA), a standard single mode fiber (SSMF) with a dispersion of 17 ps/nm/Km and a attenuation of 0.2 dB/Km.

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Coherent control of acoustic phonons in a silica fiber using a multi-GHz optical frequency comb

Communications Physics ◽

10.1038/s42005-021-00581-9 ◽

2021 ◽

Vol 4 (1) ◽

Author(s):

Mamoru Endo ◽

Shota Kimura ◽

Shuntaro Tani ◽

Yohei Kobayashi

Keyword(s):

Coherent Control ◽

Continuous Wave ◽

Frequency Comb ◽

Effective Interaction ◽

Interaction Strength ◽

Single Mode ◽

Optical Frequency Comb ◽

Material Structure ◽

Optical Frequency ◽

Acoustic Phonons

AbstractMulti-gigahertz mechanical vibrations that stem from interactions between light fields and matter—known as acoustic phonons—have long been a subject of research. In recent years, specially designed functional devices have been developed to enhance the strength of the light-matter interactions because excitation of acoustic phonons using a continuous-wave laser alone is insufficient. However, the strength of the interaction cannot be controlled appropriately or instantly using these structurally-dependent enhancements. Here we show a technique to control the effective interaction strength that does not operate via the material structure in the spatial domain; instead, the method operates through the structure of the light in the time domain. The effective excitation and coherent control of acoustic phonons in a single-mode fiber using an optical frequency comb that is performed by tailoring the optical pulse train. This work represents an important step towards comb-matter interactions.

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