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Tunable and switchable multi-wavelength Erbium-doped photonic crystal fiber ring laser incorporating a length of highly nonlinear photonic crystal fiber
Optics Communications 284 (2011) 5185–5188
Contents lists available at ScienceDirect
Optics Communications j o u r n a l h o m e p a g e : w w w. e l s ev i e r. c o m / l o c a t e / o p t c o m
Tunable and switchable multi-wavelength Erbium-doped photonic crystal fiber ring laser incorporating a length of highly nonlinear photonic crystal fiber Jianqun Cheng, Shuangchen Ruan ⁎ Shenzhen Key Laboratory of Laser Engineering, College of Electronic Science and Technology, Shenzhen University, Shenzhen, Guangdong 518060, PR China
a r t i c l e
i n f o
Article history: Received 27 February 2011 Received in revised form 28 June 2011 Accepted 7 July 2011 Available online 21 July 2011 Keywords: Fiber ring laser Erbium-doped photonic crystal fiber Highly nonlinear photonic crystal fiber Four-wave mixing effect
a b s t r a c t A tunable and switchable multi-wavelength Erbium-doped photonic crystal fiber ring laser incorporating a length of single-mode highly nonlinear photonic crystal fiber is proposed and demonstrated experimentally. Stable dual-wavelength and triple-wavelength operations at room temperature are achieved by employing the highly nonlinear photonic crystal fiber to induce four-wave mixing effect and a polarization controller to vary the polarization states of propagation lights in the laser cavity. The laser cavity is free from any wavelength selection components. The laser obtains maximal 30 dB signal-to-noise ratio and the peak power fluctuations of lasing lines are less than 1.39 dB. © 2011 Elsevier B.V. All rights reserved.
1. Introduction Multi-wavelength fiber lasers are excellent light sources in the fields such as wavelength-division-multiplexed fiber communication systems, fiber sensors, and optical instrumentations. Various techniques have been applied to realize multi-wavelength oscillations in fiber lasers by utilizing a sampled fiber Bragg grating (FBG) [1], a fiber-based triplering filter [2], a Bismuth-based Erbium-doped fiber [3], a phase-shifted phase-only sampled FBG [4], a Fabry–Perot interferometer filter and an appropriate length of normal dispersion fiber [5], a dual-pass Mach– Zehnder interferometer (MZI) filter [6]. In the last few years, photonic crystal fibers (PCFs) have attracted great interest due to their novel optical characteristics with regard to conventional fibers, such as flexible optical waveguide design, low loss, ultrahigh nonlinearity, and controllable dispersion. Highly nonlinear photonic crystal fiber (HNL-PCF) in the PCFs for having ultrahigh nonlinearity has gradually been introduced to fiber lasers. HNL-PCF coupling with a multimode FBG [7], or a sampled chirped FBG [8], or a sampled FBG [9], or a Sagnac loop filter [10,11], or a sampled Hi-Bi fiber grating [12],or an external-cavity tunable laser source [13,14] or a preamplified linear cavity structure [15] has been used in the multiwavelength fiber lasers. In this letter, we report a tunable and switchable multi-wavelength Erbium-doped photonic crystal fiber ring laser(ED-PCFRL) by inserting a
⁎ Corresponding author. E-mail address: [email protected] (S. Ruan). 0030-4018/$ – see front matter © 2011 Elsevier B.V. All rights reserved. doi:10.1016/j.optcom.2011.07.007
length of HNL-PCF in the resonant cavity to induce the four-wave mixing (FWM) effect. The proposed ED-PCFRL without any wavelength selection components can operate in a dual- wavelength or triplewavelength output by adjusting a polarization controller (PC). 2. Experiment The configuration of the proposed ED-PCFRL is shown in Fig. 1. It consists of 20 m HNL-PCF, 9 m Erbium-doped photonic crystal fiber (ED-PCF), a PC, a 20:80 fiber coupler, a 980/1550 nm wavelength division multiplexer(WDM), an optical isolator(ISO). 980 nm pump light of laser diode (LD) with 300 mW maximal output powers is coupled in the ring cavity through a 980/1550 nm WDM. The crosssection micrographs of ED-PCF and HNL-PCF are shown in Fig. 2. The ED-PCF with similar hexagonal holey cladding has a 3.34 μm mode field diameter with 0.143 numerical aperture and doping concentration of Erbium ions up to 1000 ppm. The HNL-PCF has cladding and core diameters of 122 μm and 4.6 μm, respectively. According to the crosssection structure parameters of HNL-PCF, the dispersion coefficient and nonlinear coefficient of HNL-PCF are calculated by us with finite element method. Its dispersion coefficient and nonlinear coefficient (Gamma) as a function of wavelength are shown in Fig. 3. As can be seen from it, the dispersion coefficient and nonlinear coefficient of the HNL-PCF at 980 nm are about −20 pm/nm/km and 12/W/km, respectively. The HNL-PCF has a spectral attenuation of 3 dB/km at 980 nm wavelength. In the experiment, the ED-PCF is used as linear gain medium in the resonant cavity and the HNL-PCF is employed for the generation of FWM to achieve stable multi-wavelength lasing. The PC is used to adjust the polarization states of the propagation lights across the HNL-PCF. All of the fibers in the ring cavity are single-mode fibers
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16
80 HNL-PCF
ISO 20:80 Coupler
WDM
20% Output LD
14
40
12 0 10 -40
8
-80 800
Fig. 1. Experimental setup of the proposed ED-PCFRL.
1000
1200
1400
Gamma (1/W/km)
ED-PCF
Dispersion (pm/n m/km)
PC
6 1800
1600
Wavelength(nm) Fig. 3. Dispersion coefficient and nonlinear coefficient (Gamma) of HNL-PCF verse wavelength.
(SMFs) and the PCF is carefully spliced to other SMF to decrease loss according to our design procedure. The ISO can ensure the unidirectional operation of propagation lights in the cavity. The laser output is extracted from the 20% port of the 20:80 fiber coupler and is measured by an optical spectrum analyzer with 0.05 nm resolution, the remaining 80% light is recirculated counter-clockwise around the ring.
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c
4.0x10 -5 2.0x10 -5 0.0
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Wavelength (nm) Fig. 4. Tunable dual-wavelength output spectra of the proposed ED-PCFRL.
3. Results and discussion In the experiment, by carefully adjusting the polarization state of the PC, stable dual-wavelength and triple-wavelength outputs are obtained and shown in Figs. 4 and 8, respectively. The cause is that the
b
3.0x10 2.0x10 1.0x10 0.0 1 2 3 4 5 6 7 8 9 10
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Wavelength (nm) Fig. 2. Cross-section micrographs of ED-PCF (left) and HNL-PCF (right).
Fig. 5. Stability of dual-wavelength (a).
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J. Cheng, S. Ruan / Optics Communications 284 (2011) 5185–5188
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1533.5
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Wavelength (nm)
Fig. 6. Evolution of dual-wavelength (b) under the pump powers from 132.5 mW (left) to 183 mW (right).
FWM efficiencies of different wavelengths are changed while adjusting the polarization states of propagation lights. Tunable dual-wavelength output spectra of the laser are shown in Fig. 4. It can be measured that the two lasing lines of dual-wavelength (a) in Fig. 4 locate at 1530.9 nm and 1533.3 nm and have 25 dB signalto-noise ratio (SNR). The two lasing lines of dual-wavelength (b) in Fig. 4 having 20 dB SNR locate at 1532.2 nm and 1533.3 nm, respectively. The two lasing lines of dual-wavelength (c) in Fig. 4 having 30 dB SNR locate at 1531.9 nm and 1533.7 nm, respectively. When pump power is set at 230 mW, we test the stability of dualwavelength (a). 10-time repeated scans of the laser output with 1-minute interval are carried out and shown in Fig. 5. The peak power fluctuation of lasing line with the larger intensity is less than 0.76 dB. We also test the stability of dual-wavelength (b) and investigate the evolution of dual-wavelength under the pump powers from 132.5 mW to 183 mW. 10-time repeated scans of the laser output with 1-minute interval are carried out and shown in Fig. 6. The peak power fluctuation of lasing line with the larger intensity is less than 0.35 dB. From Fig. 6, we can observe that the amplitude difference of two lasing lines decreases with pump power increasing. We test the stability of dual-wavelength (c) at the 132.5 mW pump power. 10-time repeated scans of the laser output with 1-minute interval are carried out and shown in Fig. 7. The peak power fluctuation of the right lasing line is less than 0.18 dB. As can be seen from it, the amplitude difference of both wavelengths is small.
On the other hand, by adjusting the PC, simultaneous triplewavelength output is also obtained and shown in Fig. 8. As can be seen from it, there are three different triple-wavelength outputs ((d), (e) and (f)). It can be measured that the three lasing lines of triple-wavelength (d) (black) having 20 dB SNR locate at 1531.2 nm, 1532.1 nm and 1534.1 nm, respectively. Three lasing lines of triple-wavelength (e) (red) having 20 dB SNR locate at 1531.2 nm, 1532.2 nm and 1533.3 nm, respectively. Three lasing lines of triple-wavelength (f) (blue) having 20 dB SNR locate at 1531.8 nm, 1532.7 nm and 1534.1 nm, respectively. We also test the stability of triple-wavelength (d) and investigate the evolution of three lasing lines under the pump powers from 183 mW to 278 mW. 10-time repeated scans of the laser output with 1-minute interval are carried out and shown in Fig. 9. The peak power fluctuation of lasing line at 1534.1 nm is less than 0.38 dB. From Fig. 9, we can observe that the amplitude differences of three lasing lines gradually decrease with the increment of pump power. We test the stability of triple-wavelength (e) at the pump power of 230 mW. 10-time repeated scans of the laser output with 1-minute interval are carried out and shown in Fig. 10. The peak power fluctuation of lasing line at 1533.3 nm is less than 0.23 dB. The amplitude differences of three lasing lines are less. We also test the stability of triple-wavelength (f) and investigate the evolution of three lasing lines under the pump powers from 230 mW to 278 mW. 10-time repeated scans of the laser output with 1-minute interval are carried out and shown in Fig. 11. The peak power fluctuation
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Wavelength (nm) Fig. 7. Stability of dual-wavelength (c).
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Intensity(a.u.)
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1.6x10
d e f
8.0x10-6
0.0 1530
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Wavelength (nm) Fig. 8. Tunable triple-wavelength output spectra of the proposed ED-PCFRL.
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2.0x10
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1 2 3 4 5 6 7 8 9 10
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1531
Wavelength (nm)
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Wavelength (nm)
Fig. 9. Evolution of triple-wavelength (d) under the pump powers from 183 mW (left) to 278 mW (right).
induced by a novel HNL-PCF. The proposed laser can switch between dual-wavelength and triple-wavelength output by adjusting a PC and can tune among three different lasing modes in dual-wavelength or triple-wavelength output. Repeated scans of laser output indicate that the peak power and wavelength of laser are rather stable at room temperature.
-5 -5
1.2x10
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4.0x10
Intensity(a.u.)
1.6x10
References
0.0 1 2 3 4 5 6 7 8 9 10
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1533
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Wavelength (nm) Fig. 10. Stability of triple-wavelength (e).
of lasing line at 1531.8 nm is less than 1.39 dB. From Fig. 11, we can observe that the power of 1532.7 nm wavelength increases faster than the ones of other two wavelengths with the increment of pump power. 4. Conclusion A simple tunable and switchable multi-wavelength Erbium-doped photonic crystal fiber ring laser is proposed and demonstrated. Multiwavelength lasing at room temperature stems from the FWM effect
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1.6x10
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8.0x10
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1533
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8.0x10
0.0
0.0
1 2 3 4 5 6 7 8 9 10
1 2 3 4 5 6 7 8 9 10
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1534
Wavelength (nm)
Fig. 11. Evolution of triple-wavelength (f) under the pump powers from 230 mW (left) to 278 mW (right).
Intensity(a.u.)
1531
[1] Yan-ge Liu, Xinyong Dong, Ping Shum, Shuzhong Yuan, Guiyun Kai, Xiaoyi Dong, Opt. Express 14 (2006) 9293. [2] Yeh Chien Hung, Shih Fu Yuan, Chen Chang Tai, Chi Sien, Opt. Express 15 (2007) 17980. [3] H. Ahmad, S. Shahi, S.W. Harun, Opt. Express 17 (2009) 203. [4] Ming Li, Xuxing Chen, Takeo Fujii, Yoshitaka Kudo, Hongpu Li, Yves Painchaud, Opt. Lett. 34 (2009) 1717. [5] Colm O'Riordan, Michael J. Connelly, Opt. Commun. 283 (2010) 1865. [6] Xin-LiangZhang Fei Wang, XiHuang YuYu, Opt. Laser Technol. 42 (2010) 285. [7] Feng Xinhuan, Tam Hwa-Yaw, P.K.A. Wai, IEEE Photonics Technol. Lett. 18 (2006) 1088. [8] X.M. Liu, Y. Chung, A. Lin, W. Zhao, K.Q. Lu, Y.S. Wang, T.Y. Zhang, Laser Phys. Lett. 5 (2008) 904. [9] Xiufeng Yang, Xinyong Dong, Shumin Zhang, Lu. Fuyun, Xiaoqun Zhou, Lu. Chao, IEEE Photonics Technol. Lett. 17 (2005) 2538. [10] D. Chen, Laser Phys. Lett. 4 (2007) 437. [11] Zhang Ailing, M.S. Demokan, H.Y. Tam, Opt. Commun. 260 (2006) 670. [12] Z.-Y. Liu, Y.-G. Liu, J.-B. Du, S.-Z. Yuan, X.-Y. Dong, Laser Phys. Lett. 5 (2008) 122. [13] S.W. Harun, S.N. Aziz, N. Tamchek, N.S. Shahabuddin, H. Ahmad, Electron. Lett. 44 (2008). [14] Mohd Narizee Mohd Nasir, Zulfadzli Yusoff, Mohammed Hayder Al-Mansoori, Hairul Azhar Abdul Rashid, Pankaj Kumar Choudhury, Opt. Express 17 (2009) 12829. [15] M.N. Mohd Nasir, Z. Yusoff, M.H. Al-Mansoori, H.A. Abdul Rashid, P.K. Choudhury, Laser Phys. 19 (2009) 2027.
Contents lists available at ScienceDirect
Optics Communications j o u r n a l h o m e p a g e : w w w. e l s ev i e r. c o m / l o c a t e / o p t c o m
Tunable and switchable multi-wavelength Erbium-doped photonic crystal fiber ring laser incorporating a length of highly nonlinear photonic crystal fiber Jianqun Cheng, Shuangchen Ruan ⁎ Shenzhen Key Laboratory of Laser Engineering, College of Electronic Science and Technology, Shenzhen University, Shenzhen, Guangdong 518060, PR China
a r t i c l e
i n f o
Article history: Received 27 February 2011 Received in revised form 28 June 2011 Accepted 7 July 2011 Available online 21 July 2011 Keywords: Fiber ring laser Erbium-doped photonic crystal fiber Highly nonlinear photonic crystal fiber Four-wave mixing effect
a b s t r a c t A tunable and switchable multi-wavelength Erbium-doped photonic crystal fiber ring laser incorporating a length of single-mode highly nonlinear photonic crystal fiber is proposed and demonstrated experimentally. Stable dual-wavelength and triple-wavelength operations at room temperature are achieved by employing the highly nonlinear photonic crystal fiber to induce four-wave mixing effect and a polarization controller to vary the polarization states of propagation lights in the laser cavity. The laser cavity is free from any wavelength selection components. The laser obtains maximal 30 dB signal-to-noise ratio and the peak power fluctuations of lasing lines are less than 1.39 dB. © 2011 Elsevier B.V. All rights reserved.
1. Introduction Multi-wavelength fiber lasers are excellent light sources in the fields such as wavelength-division-multiplexed fiber communication systems, fiber sensors, and optical instrumentations. Various techniques have been applied to realize multi-wavelength oscillations in fiber lasers by utilizing a sampled fiber Bragg grating (FBG) [1], a fiber-based triplering filter [2], a Bismuth-based Erbium-doped fiber [3], a phase-shifted phase-only sampled FBG [4], a Fabry–Perot interferometer filter and an appropriate length of normal dispersion fiber [5], a dual-pass Mach– Zehnder interferometer (MZI) filter [6]. In the last few years, photonic crystal fibers (PCFs) have attracted great interest due to their novel optical characteristics with regard to conventional fibers, such as flexible optical waveguide design, low loss, ultrahigh nonlinearity, and controllable dispersion. Highly nonlinear photonic crystal fiber (HNL-PCF) in the PCFs for having ultrahigh nonlinearity has gradually been introduced to fiber lasers. HNL-PCF coupling with a multimode FBG [7], or a sampled chirped FBG [8], or a sampled FBG [9], or a Sagnac loop filter [10,11], or a sampled Hi-Bi fiber grating [12],or an external-cavity tunable laser source [13,14] or a preamplified linear cavity structure [15] has been used in the multiwavelength fiber lasers. In this letter, we report a tunable and switchable multi-wavelength Erbium-doped photonic crystal fiber ring laser(ED-PCFRL) by inserting a
⁎ Corresponding author. E-mail address: [email protected] (S. Ruan). 0030-4018/$ – see front matter © 2011 Elsevier B.V. All rights reserved. doi:10.1016/j.optcom.2011.07.007
length of HNL-PCF in the resonant cavity to induce the four-wave mixing (FWM) effect. The proposed ED-PCFRL without any wavelength selection components can operate in a dual- wavelength or triplewavelength output by adjusting a polarization controller (PC). 2. Experiment The configuration of the proposed ED-PCFRL is shown in Fig. 1. It consists of 20 m HNL-PCF, 9 m Erbium-doped photonic crystal fiber (ED-PCF), a PC, a 20:80 fiber coupler, a 980/1550 nm wavelength division multiplexer(WDM), an optical isolator(ISO). 980 nm pump light of laser diode (LD) with 300 mW maximal output powers is coupled in the ring cavity through a 980/1550 nm WDM. The crosssection micrographs of ED-PCF and HNL-PCF are shown in Fig. 2. The ED-PCF with similar hexagonal holey cladding has a 3.34 μm mode field diameter with 0.143 numerical aperture and doping concentration of Erbium ions up to 1000 ppm. The HNL-PCF has cladding and core diameters of 122 μm and 4.6 μm, respectively. According to the crosssection structure parameters of HNL-PCF, the dispersion coefficient and nonlinear coefficient of HNL-PCF are calculated by us with finite element method. Its dispersion coefficient and nonlinear coefficient (Gamma) as a function of wavelength are shown in Fig. 3. As can be seen from it, the dispersion coefficient and nonlinear coefficient of the HNL-PCF at 980 nm are about −20 pm/nm/km and 12/W/km, respectively. The HNL-PCF has a spectral attenuation of 3 dB/km at 980 nm wavelength. In the experiment, the ED-PCF is used as linear gain medium in the resonant cavity and the HNL-PCF is employed for the generation of FWM to achieve stable multi-wavelength lasing. The PC is used to adjust the polarization states of the propagation lights across the HNL-PCF. All of the fibers in the ring cavity are single-mode fibers
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16
80 HNL-PCF
ISO 20:80 Coupler
WDM
20% Output LD
14
40
12 0 10 -40
8
-80 800
Fig. 1. Experimental setup of the proposed ED-PCFRL.
1000
1200
1400
Gamma (1/W/km)
ED-PCF
Dispersion (pm/n m/km)
PC
6 1800
1600
Wavelength(nm) Fig. 3. Dispersion coefficient and nonlinear coefficient (Gamma) of HNL-PCF verse wavelength.
(SMFs) and the PCF is carefully spliced to other SMF to decrease loss according to our design procedure. The ISO can ensure the unidirectional operation of propagation lights in the cavity. The laser output is extracted from the 20% port of the 20:80 fiber coupler and is measured by an optical spectrum analyzer with 0.05 nm resolution, the remaining 80% light is recirculated counter-clockwise around the ring.
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2.0x10 -5 0.0 1.5x10 -5
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a
0.0 6.0x10 -5
c
4.0x10 -5 2.0x10 -5 0.0
1530
Wavelength (nm) Fig. 4. Tunable dual-wavelength output spectra of the proposed ED-PCFRL.
3. Results and discussion In the experiment, by carefully adjusting the polarization state of the PC, stable dual-wavelength and triple-wavelength outputs are obtained and shown in Figs. 4 and 8, respectively. The cause is that the
b
3.0x10 2.0x10 1.0x10 0.0 1 2 3 4 5 6 7 8 9 10
1530
1531
1532
1533
1534
Wavelength (nm) Fig. 2. Cross-section micrographs of ED-PCF (left) and HNL-PCF (right).
Fig. 5. Stability of dual-wavelength (a).
-5 -5 -5 -5
Intensity(a.u.)
4.0x10
J. Cheng, S. Ruan / Optics Communications 284 (2011) 5185–5188
5187 -5
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8.0x10
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-6
1532.5
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1533.5
Wavelength (nm)
Wavelength (nm)
Fig. 6. Evolution of dual-wavelength (b) under the pump powers from 132.5 mW (left) to 183 mW (right).
FWM efficiencies of different wavelengths are changed while adjusting the polarization states of propagation lights. Tunable dual-wavelength output spectra of the laser are shown in Fig. 4. It can be measured that the two lasing lines of dual-wavelength (a) in Fig. 4 locate at 1530.9 nm and 1533.3 nm and have 25 dB signalto-noise ratio (SNR). The two lasing lines of dual-wavelength (b) in Fig. 4 having 20 dB SNR locate at 1532.2 nm and 1533.3 nm, respectively. The two lasing lines of dual-wavelength (c) in Fig. 4 having 30 dB SNR locate at 1531.9 nm and 1533.7 nm, respectively. When pump power is set at 230 mW, we test the stability of dualwavelength (a). 10-time repeated scans of the laser output with 1-minute interval are carried out and shown in Fig. 5. The peak power fluctuation of lasing line with the larger intensity is less than 0.76 dB. We also test the stability of dual-wavelength (b) and investigate the evolution of dual-wavelength under the pump powers from 132.5 mW to 183 mW. 10-time repeated scans of the laser output with 1-minute interval are carried out and shown in Fig. 6. The peak power fluctuation of lasing line with the larger intensity is less than 0.35 dB. From Fig. 6, we can observe that the amplitude difference of two lasing lines decreases with pump power increasing. We test the stability of dual-wavelength (c) at the 132.5 mW pump power. 10-time repeated scans of the laser output with 1-minute interval are carried out and shown in Fig. 7. The peak power fluctuation of the right lasing line is less than 0.18 dB. As can be seen from it, the amplitude difference of both wavelengths is small.
On the other hand, by adjusting the PC, simultaneous triplewavelength output is also obtained and shown in Fig. 8. As can be seen from it, there are three different triple-wavelength outputs ((d), (e) and (f)). It can be measured that the three lasing lines of triple-wavelength (d) (black) having 20 dB SNR locate at 1531.2 nm, 1532.1 nm and 1534.1 nm, respectively. Three lasing lines of triple-wavelength (e) (red) having 20 dB SNR locate at 1531.2 nm, 1532.2 nm and 1533.3 nm, respectively. Three lasing lines of triple-wavelength (f) (blue) having 20 dB SNR locate at 1531.8 nm, 1532.7 nm and 1534.1 nm, respectively. We also test the stability of triple-wavelength (d) and investigate the evolution of three lasing lines under the pump powers from 183 mW to 278 mW. 10-time repeated scans of the laser output with 1-minute interval are carried out and shown in Fig. 9. The peak power fluctuation of lasing line at 1534.1 nm is less than 0.38 dB. From Fig. 9, we can observe that the amplitude differences of three lasing lines gradually decrease with the increment of pump power. We test the stability of triple-wavelength (e) at the pump power of 230 mW. 10-time repeated scans of the laser output with 1-minute interval are carried out and shown in Fig. 10. The peak power fluctuation of lasing line at 1533.3 nm is less than 0.23 dB. The amplitude differences of three lasing lines are less. We also test the stability of triple-wavelength (f) and investigate the evolution of three lasing lines under the pump powers from 230 mW to 278 mW. 10-time repeated scans of the laser output with 1-minute interval are carried out and shown in Fig. 11. The peak power fluctuation
-5
-5
2.0x10 0.0 1 2 3 4 5 6 7 8 9 10
1532
1533
1534
Wavelength (nm) Fig. 7. Stability of dual-wavelength (c).
2.4x10-5
Intensity(a.u.)
-5
4.0x10
Intensity(a.u.)
6.0x10
-5
1.6x10
d e f
8.0x10-6
0.0 1530
1531
1532
1533
1534
1535
Wavelength (nm) Fig. 8. Tunable triple-wavelength output spectra of the proposed ED-PCFRL.
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2.0x10
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-5
-6
1 2 3 4 5 6 7 8 9 10
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1531
Wavelength (nm)
1532
1533
1534
Wavelength (nm)
Fig. 9. Evolution of triple-wavelength (d) under the pump powers from 183 mW (left) to 278 mW (right).
induced by a novel HNL-PCF. The proposed laser can switch between dual-wavelength and triple-wavelength output by adjusting a PC and can tune among three different lasing modes in dual-wavelength or triple-wavelength output. Repeated scans of laser output indicate that the peak power and wavelength of laser are rather stable at room temperature.
-5 -5
1.2x10
-6
8.0x10
-6
4.0x10
Intensity(a.u.)
1.6x10
References
0.0 1 2 3 4 5 6 7 8 9 10
1532
1533
1534
Wavelength (nm) Fig. 10. Stability of triple-wavelength (e).
of lasing line at 1531.8 nm is less than 1.39 dB. From Fig. 11, we can observe that the power of 1532.7 nm wavelength increases faster than the ones of other two wavelengths with the increment of pump power. 4. Conclusion A simple tunable and switchable multi-wavelength Erbium-doped photonic crystal fiber ring laser is proposed and demonstrated. Multiwavelength lasing at room temperature stems from the FWM effect
-5
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1.6x10
-6
8.0x10
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4.0x10
1532
1533
Wavelength (nm)
1534
-5
Intensity(a.u.)
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1.2x10
1.6x10
-6
8.0x10
0.0
0.0
1 2 3 4 5 6 7 8 9 10
1 2 3 4 5 6 7 8 9 10
1532
1533
1534
Wavelength (nm)
Fig. 11. Evolution of triple-wavelength (f) under the pump powers from 230 mW (left) to 278 mW (right).
Intensity(a.u.)
1531
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