Abstract
1 Introduction
Mode-locked thulium-doped fiber lasers (TDFLs), which operate in the 2 μm spectral region with pulse duration ranging from nanoseconds to femtoseconds, have attracted a lot of interest due to their applications in mid-infrared supercontinuum generation, remote sensing, laser processing, medicine and free-space communication[
In general,
In fact, passively mode-locked fiber lasers also can generate nanosecond pulses with high energy[
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In this paper, we will present high pulse energy nanosecond-scale passively mode-locked TDFLs with semiconductor saturable absorbers (SESAs) and carbon nanotubes (CNTs). A stable rectangular-shape DSR pulse with a maximum pulse energy up to ∼0.14 μJ was first obtained in ‘real’ SA-based mode-locked TDFL. Moreover, our experimental results verified that the SMF-MMF-SMF (SMS, SMF: SMF-28, Corning; MMF: multimode fiber, AFS105/125Y) fiber structure multimode interferometer (MMI)[
2 Experimental setup and result
In our experiment, the SMS fiber structure MMI filter was constructed by fusion splicing two pieces of SMFs at both ends of a section of ∼191 mm long MMF. The structure configuration and transmission characteristics of the fiber MMI are shown in Figures
2.1 SESA-based nanosecond mode-locked fiber laser
The experimental setup for an SESA-based nanosecond mode-locked TDFL is schematically shown in Figure
In the beginning, to verify that the SMS fiber structure MMI can function as an available wavelength selector, the SESA was not inserted into the cavity. The output properties of the fiber laser with and without the SMS fiber structure MMI are shown in Figure
Then, the SESA was sandwiched between the FC/PC ferrules, and the threshold of the mode-locked operation was about ∼2.06 W. The typical mode-locked output properties at pump power of ∼2.83 W are exhibited in Figure
In the experiment, we noted that the mode-locked pulse duration was increased with the pump powers, and the details are shown in Figure
2.2 CNTs-PVA film based nanosecond mode-locked fiber laser
Similarly to the fiber laser configuration in Figure
Maximum output | Maximum pulse | Pulse | ||||
---|---|---|---|---|---|---|
SA | Wavelength (nm) | power (mW) | energy (nJ) | duration (ns) | Reference | |
‘Real’ SA | Graphene | 1897.7–1930.2 | ∼33.9 | 35.2 | ∼122–143 | [ |
Graphene | 2010.15 | ∼5.5 | 1.4 | ∼3.8–94.3 | [ | |
CNTs | 2003.1 | ∼46 | 26.8 | ∼9.3 | Our work | |
SESA | 2002.9 | ∼461 | 141.7 | ∼1.6–9.1 | Our work | |
‘Artificial’ SA | NPR | 1960 | ∼95 | / | ∼304 | [ |
Self-mode-locking | 1985.5 | ∼66.8 | ∼32.7 | ∼40 | [ | |
NALM | 1975.56 | ∼43.1 | ∼40.5 | ∼3.74–72.19 | [ | |
NALM | 1940.2–1969.2 | ∼60.73 | ∼19.51 | ∼0.48–6.19 | [ | |
NALM | 1985 | ∼670 | ∼400 | ∼50 | [ | |
NOLM | 1948.13 | ∼295 | ∼1.5 μJ | ∼2.4–21.2 | [ | |
NOLM | 2005.9 | ∼1.4 W | ∼353 | ∼1.9–13.7 | [ | |
Intermode beating | 1983 | ∼1.03 W | ∼107 | 45 | [ |
Table 1. Comparison of output properties of 2 μm nanosecond mode-locked fiber lasers
When the CNTs-PVA film was inserted into the cavity, with proper manipulation of the PCs, the initial mode-locked operation also could be obtained. Here, we characterized the mode-locking performance at the maximum pump power of ∼2.12 W, as shown in Figure
In addition, Table
3 Conclusion
In summary, we have experimentally presented long cavity nanosecond-scale mode-locked fiber lasers with wavelength above 2 μm based on real SAs (SESA and CNTs) and SMS fiber structure MMI. The DSR pulse with output pulse energy up to ∼0.14 μJ was reported for the first time in real SA-based TDFL. This nanosecond mode-locked pulse with high pulse energy can be widely used in industrial processing and as a pump source for mid-infrared (∼3.5 μm) pulse laser generation after further amplification. Moreover, our experimental results verified the feasibility of SMS fiber structure MMI functioning as an effective wavelength filter in mode-locked TDFL.
References
[1] N. Leindecker, A. Marandi, R. L. Byer, K. L. Vodopyanov, J. Jiang, I. Hartl, M. Fermann, P. G. Schunemann. Opt. Express, 20, 7046(2012).
[2] J. Swiderski, M. Michalska, G. Maze. Opt. Express, 21, 7851(2013).
[3] C. W. Rudy, A. Marandi, K. L. Vodopyanov, R. L. Byer. Opt. Lett., 38, 2865(2013).
[4] Z. Zheng, D. Ouyang, J. Zhao, M. Liu, S. Ruan, P. Yan, J. Wang. Photon. Res., 4, 135(2016).
[5] M. Tao, T. Yu, Z. Wang, H. Chen, Y. Shen, G. Feng, X. Ye. Sci. Rep., 6, 23759(2016).
[6] K. Yin, B. Zhang, L. Yang, J. Hou. Photon. Res., 6, 123(2018).
[7] G. Ehret, C. Kiemle, M. Wirth, A. Amediek, A. Fix, S. Houweling. Appl. Phys. B, 90, 593(2008).
[8] P. Kadwani, J. Chia, F. Altal, R. A. Sims, C. Willis, L. Shah, D. Killinger, M. C. Richardson. Proc. SPIE, 7924, 79240L(2011).
[9] N. M. Fried, K. E. Murray. J. Endourol., 19, 25(2005).
[10] C. W. Rudy, M. J. F. Digonnet, R. L. Byer. Opt. Fiber Technol., 20, 642(2014).
[11] S. D. Chowdhury, A. Pal, D. Pal, S. Chatterjee, M. C. Paul, R. J. Sen, M. Pal. Opt. Lett., 42, 2471(2017).
[12] T. Hakulinen, O. G. Okhotnikov. Opt. Lett., 32, 2677(2007).
[13] M. Jiang, P. Tayebati. Opt. Lett., 32, 1797(2007).
[14] B. C. Dickinson, S. D. Jackson, T. A. King. Opt. Commun., 182, 199(2000).
[15] H. Wang, Y. Wang, W. Zhao, W. Zhang, T. Zhang, X. Hu, Z. Yang, H. Liu, K. Duan, X. Liu, C. Li, D. Shen, Z. Sui, B. Liu. Opt. Express, 18, 7263(2010).
[16] W. Chang, J. M. Soto-Crespo, A. Ankiewicz, N. Akhmediev. Phys. Rev. A, 79, 033840(2009).
[17] X. Li, X. Liu, X. Hu, L. Wang, H. Lu, Y. Wang, W. Zhao. Opt. Lett., 35, 3249(2010).
[18] L. Duan, X. Liu, D. Mao, L. Wang, G. Wang. Opt. Express, 20, 265(2012).
[19] Z. C. Luo, W. J. Cao, Z. B. Lin, Z. R. Cai, A. P. Luo, W. C. Xu. Opt. Lett., 37, 4777(2012).
[20] K. Krzempek. Opt. Express, 23, 30651(2015).
[21] J. Lee, J. Koo, J. H. Lee. Opt. Eng., 55, 081309(2016).
[22] B. Fu, L. Gui, X. Li, X. Xiao, H. Zhu, C. Yang. IEEE Photonics Technol. Lett., 25, 1447(2013).
[23] X. Wang, P. Zhou, X. Wang, H. Xiao, Z. Liu. Opt. Express, 22, 6147(2014).
[24] C. Liu, Z. Luo, Y. Huang, B. Qu, H. Cheng, Y. Wang, D. Wu, H. Xu, Z. Cai. Appl. Opt., 53, 892(2014).
[25] X. Wang, J. Zhang, Z. Gao, G. Xia, Z. Wu. Acta Phys. Sin., 66, 114209(2017).
[26] M. Wang, Y. J. Huang, J. W. Yang, Y. Zhang, S. C. Ruan. Laser Phys. Lett., 15, 085110(2018).
[27] Y. Xu, Y. Song, G. Du, P. Yan, C. Guo, G. Zheng, S. Ruan. IEEE Photonics J., 7, 1502007(2015).
[28] J. Zhao, D. Ouyang, Z. Zheng, M. Liu, X. Ren, C. Li, S. Ruan, W. Xie. Opt. Express, 24, 12072(2016).
[29] S. Kharitonov, C. Brès. 2017 European Conference on Lasers and Electro-Optics and European Quantum Electronics Conference(2017).
[30] T. Du, W. Li, Q. Ruan, K. Wang, N. Chen, Z. Luo. Appl. Phys. Express, 11, 052701(2018).
[31] M. Wang, J. Zhao, Y. Huang, S. Lin, S. Ruan. IEEE Photonics J., 9, 1506408(2017).
[32] L. Zhang, J. Hu, J. Wang, Y. Feng. Opt. Lett., 37, 3828(2012).
[33] T. Chen, Q. Zhang, Y. Zhang, X. Li, H. Zhang, W. Xia. Photon. Res., 6, 1033(2018).
[34] L. Mei, G. Chen, L. Xu, X. Zhang, C. Gu, B. Sun, A. Wang. Opt. Lett., 39, 3235(2014).
[35] J. Zhang, D. Wu, R. Zhao, R. Wang, S. Dai. High Power Laser Sci. Eng., 7, e65(2019).
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