Actively Q-switched all-fiber laser with an electrically controlled microstructured fiber Zhangwei Yu1,2, M. Malmström1,2, O. Tarasenko2, W. Margulis1,2* and F. Laurell1 1
Dept. of Applied Physics, Royal Institute of Technology (KTH), Roslagstullbacken 2, SE-106 91 Stockholm, Sweden 2 Department of Fiber Photonics, Acreo, Electrum 236, SE-164 40 Kista, Sweden *
[email protected]
Abstract: Actively Q-switching of an all-fiber laser system is demonstrated. The active element is a polarization switch with nanosecond risetime based on a microstructured fiber with electrically driven internal electrodes. Optical feedback between two 100% reflectors is inhibited until a nanosecond current pulse Q-switches the laser. After a short optical pulse develops several roundtrips later, the fiber switch is turned off, removing the short optical pulse from the cavity through a polarization splitter. Pulses of 50 W peak power and ~12 ns duration are obtained with 400 mW pump power at 100 Hz. ©2010 Optical Society of America OCIS codes: (060.2410) Fibers, erbium; (060.4005) Microstructured fibers; (140.3510) Lasers, fiber; (140.3538) Lasers, pulsed.
References and links 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11.
12. 13. 14. 15. 16. 17.
C. C. Renaud, R. J. Selvas-Aguilar, J. Nilsson, P. W. Turner, and A. B. Grudinin, “Compact high-energy Qswitched cladding-pumped fiber laser with a tuning range over 40 nm,” IEEE Photon. Technol. Lett. 11(8), 976– 978 (1999). P. Petropoulos, H. L. Offerhaus, D. J. Richardson, S. Dhanjal, and N. I. Zheludev, “Passive Q-switching of fiber lasers using a broadband liquefying gallium mirror,” Appl. Phys. Lett. 74(24), 3619–3621 (1999). R. Paschotta, R. Häring, E. Gini, H. Melchior, U. Keller, H. L. Offerhaus, and D. J. Richardson, “Passively Qswitched 0.1-mJ fiber laser system at 1.53 mum,” Opt. Lett. 24(6), 388–390 (1999). S. Kivistö, R. Koskinen, J. Paajaste, S. D. Jackson, M. Guina, and O. G. Okhotnikov, “Passively Q-switched Tm3+, Ho3+-doped silica fiber laser using a highly nonlinear saturable absorber and dynamic gain pulse compression,” Opt. Express 16(26), 22058–22063 (2008). T.-Y. Tsai, and Y.-C. Fang, “A saturable absorber Q-switched all-fiber ring laser,” Opt. Express 17(3), 1429– 1434 (2009). T.-Y. Tsai, and Y.-C. Fang, “A self-Q-switched all-fiber erbium laser at 1530 nm using an auxiliary 1570-nm erbium laser,” Opt. Express 17(24), 21628–21633 (2009). T.-Y. Tsai, Y.-C. Fang, Z.-C. Lee, and H.-X. Tsao, “All-fiber passively Q-switched erbium laser using mismatch of mode field areas and a saturable-amplifier pump switch,” Opt. Lett. 34(19), 2891–2893 (2009). S. V. Chernikov, Y. Zhu, J. R. Taylor, and V. P. Gapontsev, “Supercontinuum self-Q-switched ytterbium fiber laser,” Opt. Lett. 22(5), 298–300 (1997). A. A. Fotiadi, O. Deparis, R. Kiyan, S. Chernikov, and A. Ikiades, “Dynamics of passive Q-switching in SBS/Er fiber laser at low pump power,” Proc. SPIE 4354, 125–134 (2001). Z. Pan, L. Meng, Q. Ye, H. Cai, Z. Fang, and R. Qu, “Repetition rate stabilization of the SBS Q-switched fiber laser by external injection,” Opt. Express 17(5), 3124–3129 (2009). P. Dupriez, A. Piper, A. Malinowski, J. K. Sahu, M. Ibsen, B. C. Thomsen, Y. Jeong, L. M. B. Hickey, M. N. Zervas, J. Nilsson, and D. J. Richardson, “High average power, high repetition rate, picosecond pulsed fiber master oscillator power amplifier source seeded by a gain-switched laser diode at 1060 nm,” IEEE Photon. Technol. Lett. 18(9), 1013–1015 (2006). A. Chandonnet, and G. Larose, “High-power Q-switched erbium fiber laser using an all-fiber intensity modulator,” Opt. Eng. 32(9), 2031–2035 (1993). D.-W. Huang, W.-F. Liu, and C. C. Yang, “Q-switched all-fiber laser with an acoustically modulated fiber attenuator,” IEEE Photon. Technol. Lett. 12(9), 1153–1155 (2000). D. Zalvidea, N. A. Russo, R. Duchowicz, M. Delgado-Pinar, A. Díez, J. L. Cruz, and M. V. Andrés, “Highrepetition rate acoustic-induced Q-switched all-fiber laser,” Opt. Commun. 244(1-6), 315–319 (2005). C. Cuadrado-Laborde, M. Delgado-Pinar, S. Torres-Peiró, A. Díez, and M. V. Andrés, “Q-switched all-fiber laser using a fibre-optic resonant acousto-optic modulator,” Opt. Commun. 274(2), 407–411 (2007). K. Kieu, and M. Mansuripur, “Active Q switching of a fiber laser with a microsphere resonator,” Opt. Lett. 31(24), 3568–3570 (2006). M. Delgado-Pinar, D. Zalvidea, A. Díez, P. Pérez-Millan, and M. V. Andrés, “Q-switching of an all-fiber laser by acousto-optic modulation of a fiber Bragg grating,” Opt. Express 14(3), 1106–1112 (2006).
#125395 - $15.00 USD Received 12 Mar 2010; revised 30 Apr 2010; accepted 30 Apr 2010; published 11 May 2010
(C) 2010 OSA
24 May 2010 / Vol. 18, No. 11 / OPTICS EXPRESS 11052
18. M. V. Andrés, J. L. Cruz, A. Díez, P. Pérez-Millán, and M. Delgado-Pinar, “Actively Q-switched all-fiber lasers,” Laser Phys. Lett. 5(2), 93–99 (2008). 19. C. Cuadrado-Laborde, A. Díez, J. L. Cruz, and M. V. Andrés, “Doubly active Q switching and mode locking of an all-fiber laser,” Opt. Lett. 34(18), 2709–2711 (2009). 20. N. A. Russo, R. Duchowicz, J. Mora, J. L. Cruz, and M. V. Andrés, “High-efficient Q-switched erbium fiber laser using a Bragg grating-based modulator,” Opt. Commun. 210(3-6), 361–366 (2002). 21. X. P. Cheng, C. H. Tse, P. Shum, R. F. Wu, M. Tang, W. C. Tan, and J. Zhang, “All-Fiber Q-Switched erbiumdoped fiber ring laser using phase-shifted fiber Bragg grating,” J. Lightwave Technol. 26(8), 945–951 (2008). 22. P. Pérez-Millán, A. Díez, M. V. Andrés, D. Zalvidea, and R. Duchowicz, “Q-switched all-fiber laser based on magnetostriction modulation of a Bragg grating,” Opt. Express 13(13), 5046–5051 (2005). 23. F.-W. Sheu, and J.-J. Kang, “All-fiber actively Q-switched fiber laser tuned by a pair of temperature controlled fiber Bragg gratings,” Opt. Commun. 278(1), 132–137 (2007). 24. M. Malmström, Z. Yu, W. Margulis, O. Tarasenko, and F. Laurell, “All-fiber cavity dumping,” Opt. Express 17(20), 17596–17602 (2009). 25. H. Knape, and W. Margulis, “All-fiber polarization switch,” Opt. Lett. 32(6), 614–616 (2007). 26. Z. Yu, H. Knape, O. Tarasenko, R. Koch, and W. Margulis, “All-fiber single-pulse selection and nanosecond gating,” Opt. Lett. 34(7), 1024–1026 (2009). 27. A. Gusarov, N. H. Ky, H. G. Limberger, R. P. Salathe, and G. R. Fox, “High-performance optical phase modulation using piezoelectric ZnO-coated standard telecommunication fiber,” J. Lightwave Technol. 14(12), 2771–2777 (1996). 28. M. Malmström, W. Margulis, Z. Yu, O. Tarasenko, and F. Laurell, “All-fiber Q-switched and cavity dumped laser using an electrically addressed microstructured fiber,” in Advanced Solid-State Conference, Technical Digest (CD) (Optical Society of America, 2010), paper AMB8). http://www.opticsinfobase.org/abstract.cfm?URI=ASSP-2010-AMB8
1. Introduction Q-switching of fiber lasers is an established technique to generate short pulses with high peak power and has many applications, such as optical time-domain reflectometry, material processing, remote sensing and nonlinear optical frequency conversion [1,2]. All-fiber devices for Q-switching are advantageous due to their alignment-free characteristics and lower cavity loss. Although passive Q-switching usually involves a simple laser cavity and produces highpower short duration pulses [3–10], the repetition frequency and the pulse timing are often uncontrolled. In contrast, active Q-switching uses external means to determine the loss of the laser cavity and allows for more control over the characteristics of the output pulses. Therefore, actively Q-switched lasers are the usual choice for industrial applications. The most common scheme for producing high power pulses from a fiber laser is the master oscillator power amplifier (MOPA) configuration, where a semiconductor laser pulse seeds a fiber power amplifier [11]. This technique is very powerful and is widely used. However, the MOPA configuration also has its weak points, such as the need for a few amplifying stages and very careful isolation of the seed laser from feedback. This motivates the search for a simpler Q-switching scheme that allows for the direct generation of a high-power short duration pulse by a fiber laser. This could potentially eliminate the need for some of the amplifier stages and a sensitive semiconductor laser diode seed. In the last years, several successful all-fiber approaches based on different modulation techniques have been reported, such as all-fiber intensity modulators [12], all-fiber acousto-optic attenuators [13–15], and a microsphere resonator [16]. Q-switching of all-fiber lasers has been accomplished by tuning fiber Bragg grating (FBG) using acousto-optic modulators [17–19], piezoelectric actuators [20,21], magnetostrictive transducers [22], and temperature controllers [23]. Problems with these methods include mechanical relaxation, hysteresis, slow rise- and falltime and low extinction ratio. In our previous work, a microstructured fiber with electrically driven internal electrodes has been employed to cavity dump an all-fiber erbium-doped ring laser [24]. The internal electrode fiber component allows for polarization rotation of light guided in the core with a risetime
