A theoretical study of double-pass thulium-doped fiber amplifiers

• Published in: Optik (Stuttgart) Vol. 121; no. 14; pp. 1257 - 1262
• Main Authors: Emami, S.D., Harun, S.W., Abd-Rahman, F., Abdul-Rashid, H.A., Daud, S.A., Ghani, Z.A., Ahmad, H.
• Format: Journal Article
• Language: English
• Published: Reutlingen Elsevier GmbH 01-08-2010; Elsevier
• Subjects: Amplification; Amplifiers; Differential equations; Double pass; Exact sciences and technology; Fibers; Fundamental areas of phenomenology (including applications); Gain; Noise levels; Optical elements, devices, and systems; Optics; Physics; Pumps; Reflectors, beam splitters, and deflectors; Runge-Kutta method; S-band amplifier; Thulium-doped fiber amplifier; Thulium-doped fiber amplifier; S-band amplifier; Double pass; Optical fibers; Thulium-doped fibers; Reflectors; Differential equations; Runge-Kutta methods
• ISSN: 0030-4026; 1618-1336
• DOI: 10.1016/j.ijleo.2009.01.017

An efficient fluoride-based thulium-doped fiber amplifier (TDFA) is theoretically demonstrated using a double-pass scheme. A reflector is incorporated in the double-pass TDFA to allow double propagation of the test signal in the gain medium and thus improve the gain of the TDFA. The small signal gain improvement of more than 15
dB is obtained in the 1465
nm region. A gain as high as 42
dB is obtained in this region with 300
mW of 1050
nm pump using 20
m of thulium-doped fiber. However, a noise figure penalty of approximately 1
dB is also obtained in this wavelength region. Differential equations are solved using the Runge–Kutta method in the theoretical analysis. The theoretical result is in agreement with the experimental result.