Citation: | Hu Xiaolin, Yan Zhijun, Huang Qianqian, et al. Wavelength-tunable Q-switched fiber laser based on a 45° tilted fiber grating[J]. Opto-Electronic Engineering, 2018, 45(10): 170741. doi: 10.12086/oee.2018.170741 |
[1] | Mears R J, Reekie L, Poole S B, et al. Low-threshold tunable CW and Q-switched fibre laser operating at 1.55μm[J]. Electronics Letters, 1986, 22(3): 159-160. doi: 10.1049/el:19860111 |
[2] | Luo Z Q, Liu C, Huang Y Z, et al. Topological-insulator passively Q-switched double-clad fiber laser at 2μm wavelength[J]. IEEE Journal of Selected Topics in Quantum Electronics, 2014, 20(5): 1-8. doi: 10.1109/JSTQE.2014.2305834 |
[3] | Wang L, Gao C Q, Gao M W, et al. A resonantly-pumped tunable Q-switched Ho: YAG ceramic laser with diffraction-limit beam quality[J]. Optics Express, 2014, 22(1): 254-261. doi: 10.1364/OE.22.000254 |
[4] | Sharma U, Kim C S, Kang J U, et al. Highly stable tunable dual-wavelength Q-switched fiber laser for DIAL applications[C]//Proceedings of 2004 Laser Applications to Chemical and Environmental Analysis, Annapolis, Maryland United States, 2004: 1277-1279. |
[5] | Chernikov S V, Zhu Y, Taylor J R, et al. Supercontinuum self-Q-switched ytterbium fiber laser[J]. Optics Letters, 1997, 22(5): 298-300. doi: 10.1364/OL.22.000298 |
[6] | Dong B, Hao J Z, Hu J H, et al. Wide pulse-repetition-rate range tunable nanotube Q-switched low threshold erbium-doped fiber laser[J]. IEEE Photonics Technology Letters, 2010, 22(24): 1853-1855. |
[7] | Pérez-Millán P, Cruz J L, Andrés M V. Active Q-switched distributed feedback erbium-doped fiber lasers[J]. Applied Physics Letters, 2005, 87(1): 011104. doi: 10.1063/1.1990252 |
[8] | Delgado-Pinar M, Díez A, Cruz J L, et al. Single-frequency active Q-switched distributed fiber laser using acoustic waves[J]. Applied Physics Letters, 2007, 90(17): 171110. doi: 10.1063/1.2732832 |
[9] | Keller U, Weingarten K J, Kartner F X, et al. Semiconductor saturable absorber mirrors (SESAM's) for femtosecond to nanosecond pulse generation in solid-state lasers[J]. IEEE Journal of Selected Topics in Quantum Electronics, 1996, 2(3): 435-453. doi: 10.1109/2944.571743 |
[10] | Li J F, Hudson D D, Liu Y, et al. Efficient 2.87 μm fiber laser passively switched using a semiconductor saturable absorber mirror[J]. Optics Letters, 2012, 37(18): 3747-3749. doi: 10.1364/OL.37.003747 |
[11] | Filippov V N, Starodumov A N, Kir'yanov A V. All-fiber passively Q-switched low-threshold erbium laser[J]. Optics Letters, 2001, 26(6): 343-345. doi: 10.1364/OL.26.000343 |
[12] | Laroche M, Chardon A M, Nilsson J, et al. Compact diode-pumped passively Q-switched tunable Er-Yb double-clad fiber laser[J]. Optics Letters, 2002, 27(22): 1980-1982. doi: 10.1364/OL.27.001980 |
[13] | Zhou D P, Wei L, Dong B, et al. Tunable passively Q-switched erbium-doped fiber laser with carbon nanotubes as a saturable absorber[J]. IEEE Photonics Technology Letters, 2010, 22(1): 9-11. doi: 10.1109/LPT.2009.2035325 |
[14] | Cao W J, Wang H Y, Luo A P, et al. Graphene-based, 50 nm wide-band tunable passively Q-switched fiber laser[J]. Laser Physics Letters, 2011, 9(1): 54-58. doi: 10.1002/lapl.201110085 |
[15] | Luo Z C, Liu J R, Wang H Y, et al. Wide-band tunable passively Q-switched all-fiber ring laser based on nonlinear polarization rotation technique[J]. Laser Physics, 2012, 22(1): 203-206. doi: 10.1134/S1054660X11230125 |
[16] | Wang T X, Yan Z J, Mou C B, et al. Stable nanosecond passively Q-switched all-fiber erbium-doped laser with a 45° tilted fiber grating[J]. Applied Optics, 2017, 56(12): 3583-3588. doi: 10.1364/AO.56.003583 |
[17] | Yan Z J, Mou C B, Zhou K M, et al. UV-inscription, polarization-dependant loss characteristics and applications of 45° tilted fiber gratings[J]. Journal of Lightwave Technology, 2011, 29(18): 2715-2724. doi: 10.1109/JLT.2011.2163196 |
[18] | Yan Z J, Mou C B, Wang H S, et al. All-fiber polarization interference filters based on 45°-tilted fiber gratings[J]. Optics Letters, 2012, 37(3): 353-355. doi: 10.1364/OL.37.000353 |
[19] | Zhou K M, Cheng X F, Yan Z J, et al. Optical Spectrum Analyzer using a 45° tilted fiber grating[C]//Proceedings of 2012 Advanced Photonics Congress, Colorado Springs, Colorado, United States, 2012: BW2E. 7. |
[20] | Yan Z J, Mou C B, Sun Z Y, et al. Hybrid tilted fiber grating based refractive index and liquid level sensing system[J]. Optics Communications, 2015, 351: 144-148. doi: 10.1016/j.optcom.2015.04.038 |
[21] | Zhou K M, Simpson G, Chen X F, et al. High extinction ratio in-fiber polarizers based on 45° tilted fiber Bragg gratings[J]. Optics Letters, 2005, 30(11): 1285-1287. doi: 10.1364/OL.30.001285 |
[22] | Renaud C C, Selvas-Aguilar R J, Nilsson J, et al. Compact high-energy Q-switched cladding-pumped fiber laser with a tuning range over 40 nm[J]. IEEE Photonics Technology Letters, 1999, 11(8): 976-978. doi: 10.1109/68.775318 |
[23] | Fan Y X, Lu F Y, Hu S L, et al. Tunable high-peak-power, high-energy hybrid Q-switched double-clad fiber laser[J]. Optics Letters, 2004, 29(7): 724-726. doi: 10.1364/OL.29.000724 |
[24] | Popa D, Sun Z, Hasan T, et al. Graphene Q-switched, tunable fiber laser[J]. Applied Physics Letters, 2011, 98(7): 073106. doi: 10.1063/1.3552684 |
[25] | Chen Y, Zhao C J, Chen S Q, et al. Large energy, wavelength widely tunable, topological insulator Q-switched erbium-doped fiber laser[J]. IEEE Journal of Selected Topics in Quantum Electronics, 2014, 20(5): 315-322. doi: 10.1109/JSTQE.2013.2295196 |
[26] | Huang Y Z, Luo Z Q, Li Y Y, et al. Widely-tunable, passively Q-switched erbium-doped fiber laser with few-layer MoS2 saturable absorber[J]. Optics Express, 2014, 22(21): 25258-25266. doi: 10.1364/OE.22.025258 |
[27] | Woodward R I, Kelleher E J R, Howe R C T, et al. Tunable Q-switched fiber laser based on saturable edge-state absorption in few-layer molybdenum disulfide (MoS2)[J]. Optics Express, 2014, 22(25): 31113-31122. doi: 10.1364/OE.22.031113 |
[28] | Mou C B, Zhou K M, Zhang L, et al. Characterization of 45°-tilted fiber grating and its polarization function in fiber ring laser[J]. Journal of the Optical Society of America B, 2009, 26(10): 1905-1911. doi: 10.1364/JOSAB.26.001905 |
[29] | Hönninger C, Paschotta R, Morier-Genoud F, et al.Q-switching stability limits of continuous-wave passive mode locking[J]. Journal of the Optical Society of America B, 1999, 16(1): 46-56. doi: 10.1364/JOSAB.16.000046 |
Overview: Wavelength tunable Q-switched fiber lasers have important applications in the fields of communication, medicine, ranging finding and laser processing. Generally speaking, Q-switched fiber lasers can be divided into two types using either active or passive system. There are several kinds of saturable absorber can be used to realize passively Q-switched in fiber lasers, including semiconductor saturable absorber mirrors (SESAMs), transition metal-doped crystals and single-wall carbon nanotubes (SWNTs). However, the method of using nonlinear polarization rotation (NPR) technology which is an artificial saturable absorber to realize passively Q-switched can not only maintain all-fiber structure of fiber lasers, but also change the width of Q-switched pulses by adjusting the states of polarization controllers. By regulating commercial bandpass filter, the central wavelength of the Q-switched pulses can be adjusted continuously in a larger range.
In this paper, a continuously tunable Q-switched all-fiber Er-doped laser based on a 45°-tilted fiber grating and tunable bandpass filter is demonstrated. The 45°-tilted fiber grating is used to achieve the nonlinear polarization rotation (NPR) along with two polarization controllers (PCs). In this experiment, the fiber grating is equivalent to an ideal in-fiber polarizer because it has strong polarization-dependent loss (PDL), then the Q-switched pulses can be easily observed by properly adjusting the polarization controllers. Under the pump power of 655 mW, stable Q-switched pulses with central wavelength of 1548 nm, average output power of 4.45 mW, repetition rate of 105 kHz, and signal to noise ratio (SNR) of 39.89 dB are obtained. Furthermore, the Q-switched optical spectrum can be continuously tuned from 1512 nm to 1552 nm by simply rotating the tunable bandpass filter with 655 mW pump power. As far as we know, this is the widest tunable range of tunable Q-switched fiber Lasers based on nonlinear polarization rotation effect and tunable bandpass filter.
Measured insertion loss of the 45° TFG from 1525 nm to 1608 nm. (a) Insertion loss; (b) PDL response
Spectral characteristics of tunable bandpass filter. (a) 1512 nm~1552 nm; (b) 1548 nm
Schematic diagram of the wavelength-tunable Q-switched fiber laser based on a 45° tilted fiber grating
Measured characteristics of Q-switched fiber laser under the pump power of 655 mW. (a) Optical spectrum shift; (b) Optical spectrum; (c) Pulse trains; (d) Profile; (e) RF spectrum with a 200 kHz span, inset presents the RF spectrum with a 500 kHz span; (f) The laser output power and repetition rate variations along with elevating pump power