摘要： Exploring the new wavelength bands is of great importance for many different applications such as medicine, astronomy, material processing, defence and optical fiber communication. Ytterbium (Yb), Erbium (Er), and Thulium (Tm) or Holmium (Ho)- doped fibers covers the wavelength bands around 1, 1.5 and 2μm, respectively. However, the band between Yb and Er is mostly not covered by the rare earth (RE)-doped silica fibers. Recent years, there is a growing interest to use Bi-doped fibers with different host materials such as aluminosilicate, phosphosilicate and germanosilicate to explore the wavelength band from 1150-1500nm. Also, Bi-doped germanosilicate fibers with a high concentration of germanium (up to 50mol%) were used to cover the band from 1600-1800nm. Many optoelectronic devices including amplifiers, lasers, amplified spontaneous emission (ASE) sources and pulsed lasers were reported using Bi-doped fibers [1-3]. However, less work is being done to develop tunable Bi-doped fiber lasers. Using a Bi-doped germanosilicate fiber a tunable laser operating from 1360 to 1510nm was reported. The cavity was formed by a loop reflector and an external plane diffraction grating [4]. In this paper, we demonstrate a tunable laser operating in 1317 to 1375nm band using Bi-doped phosphosilicate fiber fabricated in-house using modified chemical vapour deposition (MCVD)-solution doping technique. The fiber has a core and clad diameter of 9μm and 125μm, respectively. The index difference (Δn) between the core and clad was around 0.004. The absorption at 1270nm pump wavelength was 0.57dB/m.