Gain and noise figure enhancement of Er+3/Yb+3 co-doped fiber/Raman hybrid amplifier

• Er/Yb co-doped/Raman hybrid amplifier was purposed at different values of input pump powers.
• The gain and noise figure of Er/Yb co-doped is improved due to hybrid with Raman amplifier.
• The most applications of such hybrid are high transmission capacity DWDM.
• The higher values of bandwidth are obtained due to hybrid Raman which is more important in DWDM.

An Er/Yb co-doped fiber/Raman hybrid amplifier (HA) is proposed and studied theoretically and analytically to improve the gain and noise figure of optical amplifiers. The calculations are performed under a uniform dopant and steady-state conditions. The initial energy transfer efficiency for Er/Yb co-doped fiber amplifier (EYDFA) is introduced, while the amplified spontaneous emission (ASE) is neglected. The glass fiber used for both Er/Yb and Raman amplifiers is phosphate. Different pump powers are used for both EYDFA and RA with 1 μW input signal power, 1 m length of Er/Yb amplifier and 25 km length of Raman amplifier (RA). The proposed model is validated for Er/Yb co-doped amplifier and Raman amplifier separately by comparing the calculating results with the experimental data. A high gain and low noise figure at 200 mW Raman pump power and 500 mW Er/Yb pump power are obtained for the proposed HA as compared with the experimental results of EYDFA, Raman amplifier and the EDFA/Raman hybrid amplifier.