We discuss the numerical modelling of lanthanide-ion doped chalcogenide glass fibre lasers for operation in the mid-infrared wavelength region. We extract the modelling parameters from emission and absorption measurements using Judd-Ofelt and McCumber theory. Numerical algorithms are developed based on the experimentally extracted fibre parameters. The simulation results predict lasing with slope efficiency of at least 20 % provided, that the fibre loss can be kept at the level of 1 dB/m or less

Barney, Emma R.

Benson, Trevor M.

Fuhrberg, P.

Furniss, David

Lamrini, S.

Sakr, H.

Scholle, K.

Seddon, Angela B.

Sujecki, S.

Sójka, L.

Tang, Zhuoqi

Nottingham ePrints

Sójka, L. and Furniss, David and Tang, Zhuoqi and Sakr, H. and Barney, Emma R. and Benson, Trevor M. and Seddon, Angela B. and Sujecki, S. and Scholle, K. and Lamrini, S. and Fuhrberg, P. (2016) Numerical modeling of lathanide-ion doped fibre lasers operating within mid-infrared wavelength region. In: 18th International Conference on Transparent Optical Networks, 10-14 July 2016, Trento, Italy. Access from the University of Nottingham repository: http://eprints.nottingham.ac.uk/35545/1/ICTON_2016_v5.pdfCopyright and reuse: The Nottingham ePrints service makes this work by researchers of the University of Nottingham available open access under the following conditions.This article is made available under the University of Nottingham End User licence and may be reused according to the conditions of the licence.  For more details see: http://eprints.nottingham.ac.uk/end_user_agreement.pdfA note on versions: The version presented here may differ from the published version or from the version of record. If you wish to cite this item you are advised to consult the publisher’s version. Please see the repository url above for details on accessing the published version and note that access may require a subscription.For more information, please contact eprints@nottingham.ac.ukNumerical modelling of lanthanide-ion doped fibre lasers operating within mid-infrared wavelength region Ł. Sójka1, D. Furniss1, Z. Tang1, H. Sakr1, E. Barney1, T.M. Benson1, A.B. Seddon1, S. Sujecki1, K. Scholle2, S. Lamrini2 and P. Fuhrberg2  1George Green Institute for Electromagnetics Research, University of Nottingham, University Park, NG7 2RD Nottingham, UK, Tel: (+44115) 9515550, Fax: (+44115) 9515616, e-mail: Slawomir.Sujecki@notingham.ac.uk  2LISA laser products OHG Fuhrberg & Teichmann  Max-Planck-Str. 1 D- 37191 Katlenburg-Lindau Germany   ABSTRACT We discuss the numerical modelling of lanthanide-ion doped chalcogenide glass fibre lasers for operation in the mid-infrared wavelength region. We extract the modelling parameters from emission and absorption measurements using Judd-Ofelt and McCumber theory. Numerical algorithms are developed based on the experimentally extracted fibre parameters. The simulation results predict lasing with slope efficiency of at least 20 % provided, that the fibre loss can be kept at the level of 1 dB/m or less.  Keywords: fibre laser modelling, mid-infrared light, numerical modelling. 1. INTRODUCTION Mid-infrared (MIR) coherent light sources are relevant to many potential markets that include medicine, environmental monitoring, pharmaceutical industry, etc. Currently available MIR lasers include quantum cascade lasers (QCLs), optical parametric oscillators (OPOs), difference frequency generation (DFG) sources, solid state, fibre and gas lasers. MIR fibre lasers potentially offer good quality of the output beam, large wavelength tuning ability, pulsed operation, relatively large pumping efficiency and contained beam delivery. The longest lasing wavelength that has so far been achieved by a lanthanide ion doped fibre laser is 3.9 m [1]. A Ho3+ doped fluoride (ZBLAN) fibre was used for this purpose and there was a need to apply liquid nitrogen cooling. For many applications liquid nitrogen cooling would impose a severe impediment. Hence, considerable effort has been invested into developing MIR fibre lasers for room temperature operation [2-4]. In 2014 an Er3+ ion doped ZBLAN fibre laser was demonstrated, which operates at room temperature at 3.604 m [3], while in [4] successfully development of a ZBLAN fibre laser with output power in excess of 1 W at 3.44 m was presented. Further, increase of the ZBLAN fibre laser room temperature operating wavelength is impeded by the relatively high glass matrix maximum phonon energy. Therefore, in order to access longer fibre lasing wavelengths, fibres with a lower maximum phonon energy must be developed. One of the promising candidates for achieving this is the chalcogenide glass family. There is a large body of literature reporting strong MIR photoluminescence (PL), extending up to nearly 6 m, from lanthanide ion doped chalcogenide glass fibre and bulk samples [5-10]. Chalcogenide fibres are chemically stable, mechanically robust and can attain a low attenuation within the MIR wavelength range [11, 12]. Moreover, Raman lasers based on chalcogenide glass fibres with operating wavelengths up to 3.77 m have been demonstrated [13, 14]. Finally, recently in [15], chalcogenide fibre has been reported to be successfully thermally spliced with silica fibre thus facilitating the coupling of pump power from a commercially available pig-tailed laser diode [15]. All of these achievements show the potential of the lanthanide ion doped chalcogenide glass fibre technology for the realisation of MIR lasers. The theoretical studies carried out to date show that lanthanide ion doped chalcogenide glass fibre lasers could potentially achieve a wall plug efficiency of up to 20 % when using a cascade pumping scheme [16-18]. Here, we present numerical modelling of alternative pumping schemes for chalcogenide glass lanthanide doped fibre lasers. We studied the properties of a Pr3+ doped chalcogenide glass fibre laser that is resonantly pumped using a quantum cascade laser (QCL) and a 3 level lasing system realised by doping selenide based chalcogenide glass with Tb3+ ions. Numerical modelling results confirmed the advantages of both pumping schemes when compared with the cascade pumping schemes of [16-18]. 2. MODEL DESCRIPTION For the Tb3+ doped glass fibre laser pumped at 2.013 m or 2.95 m (Fig.1 and Fig.2, respectively), the energy level populations are obtained from:   013133323  NNWNW pepa  (1a)   013232211  NNWNW sesa  (1b) TbNNNN  321  (1c) while for the Pr3+ doped glass fibre laser (Fig.3) the energy level populations are calculated by solving:   011 332312  NWNW eseesa   (2a)       011 1322211  NWNWWWNWW eseesapesepasa   (2b) Pr321 NNNN   (2c) where NTb and NPr is the Tb3+ and Pr3+ dopant ion concentration, respectively. The symbols i denote level i lifetime. The excited state absorption rate and the stimulated emission rate are calculated from:    ppeffesappesa PPNhcAW 2;    ppeffeseppese PPNhcAW 3 (3a)    ppeffpapppa PPNhcAW 1;    ppeffpepppe PPNhcAW 2 (3b)    sseffsasssa PPNhcAW 1;    sseffsessse PPNhcAW 2 (3c) The evolution of the pump and signal powers (Pp and Ps respectively) is described by the equations:      pppesaeseppapeppPPNNPNNzP 2312  (4a)    sssaess PPNNzP 121221  (4b) The partial differential equations (4) are solved subject to the following boundary conditions:          pumppppp PzRzPzRzP 01000    (5a)      LzPLzRLzP ppp  (5b)      000   zPzRzP sss  (5c)      LzPLzRLzP sss  (5d) where L is the cavity length, Rp and Rs are the facet power reflectivity for the pump and signal waves, respectively, while Ppump stands for the pump power launched into the fibre at z = 0 (Fig.4). We solved equations (1-4) using the relaxation method (RM) [19] due to its robustness.  3. NUMERICAL RESULTS In Tables 1-3 we list the modelling parameters. The values of emission and absorption cross sections were obtained from experimental Fourier Transform Infrared (FTIR) spectroscopy measurements of bulk chalcogenide glass samples doped with terbium and praseodymium ions which were prepared in house. The respective emission cross-sections were obtained from the absorption cross-section spectra using McCumber theory and were verified by experimentally measuring PL spectra. The radiative lifetimes were obtained by applying Judd-Ofelt theory to FTIR results and verified by PL lifetime measurements. The excited state absorption spectrum was extracted using McCumber theory from  PL spectra measured in [6]. The non-radiative lifetimes resulting from phonon assisted transitions were extracted by fitting the experimental results taken from [6-8].  The modelled example fibre laser structure consisted of a length of a fibre pumped at one side (Fig.4). In the model, fibre gratings trapped the signal and pump light within the fibre cavity. Figure 5 shows the dependence of the MIR signal wave power on the pump power that was calculated using the developed model. These numerical results predicted that when using all three pumping methods an achievement of slope efficiency of at least 20 % is possible.  ACKNOWLEGMENTS This research has been supported by the European Commission through FP7 Project MINERVA (317803; www.minerva-project.eu): Mid- to NEaR infrared spectroscopy for improved medical diAgnostics and EPSRC pump priming grant RDF/0312: Three level lasing host for mid infrared (MIR) generation.  Table 1. Modelling parameters for Tb3+.  parameter Unit value 31(p=2.013 m) ms 0.012  21(p=2.013 m) ms 10.18  32(p=2.013 m) ms 0.0119  31(p=2.95 m) ms 0.012  21(p=2. 95 m) ms 10.18  32(p=2. 95 m) ms 0.012 pa(p=2.013 m) m2 0.73×10-24 pe(p=2.013 m) m2 0.7×10-24 pa(p=2.95 m) m2 1.03×10-24 pe(p=2.95 m) m2 0.53×10-24 sa m2 1.47×10-24 se m2 1.00×10-24 s m 4.7x10-6  Table 2. Modelling parameters for Pr3+. Parameter Unit value 31 ms 3.53  21 ms 10.1 32 ms 8.027 esa m2 0.306×10-24 ese m2 0.896×10-24 pa m2 0.622×10-24 pe m2 1.711×10-24 sa m2 0.376×10-24 se m2 0.849×10-24 p m 4.15x10-6 s m 4.9x10-6  Table 3. Fiber laser modelling parameters.  Parameter Unit value NTb NPr 1/ m3 0.825×1025 0.96x1025 L m 1.0 p  0.9 s  0.9 p 1/m 0.23 s 1/m 0.23 Rp(z=0)  0.05 Rp(z=L)  0.95 Rs(z=0)  0.05 Rs(z=L)  0.95    Fig.1. Schematic diagram of energy levels of Tb3+ pumped at 2.95 m.    Fig.2. Schematic diagram of energy levels of Tb3+ pumped at 2.013 m.     Fig.3. Schematic diagram of energy levels of Pr3+ pumped resonantly at 4.15 m.    Fig.4. Modelled fibre laser structure; Fibre gratings FG1 and FG2 trap the signal and the pump, respectively, within the cavity.   Fig.5. Dependence of the MIR signal power on the pump power for the fibre laser structure from Fig.4. REFERENCES  [1] J. Schneider, C. Carbonnier, and U. B. Unrau, "Characterization of a Ho3+-doped fluoride fiber laser with a 3.9-m emission wavelength," Applied Optics 36, 8595-8600 (1997). [2] C. Carbonnier, H. Tobben, and U. B. Unrau, "Room temperature CW fibre laser at 3.22 m," Electronics Letters 34, 893-894 (1998). [3] O. Henderson-Sapir, J. Munch, and D. J. Ottaway, "Mid-infrared fiber lasers at and beyond 3.5 m using dual-wavelength pumping," Optics Letters 39, 493-496 (2014). [4] V. Fortin, F. Maes, M. Bernier, S. Tobou Bah, M. D'Auteuil, and R. Vallee, "Watt-level erbium-doped all-fiber laser at 3.44 m," accepted for publication, Optics Letters (2016). [5] J. S. Sanghera, L. B. Shaw, and I. D. Aggarwal, "Chalcogenide Glass-Fiber-Based Mid-IR Sources and Applications," Ieee Journal of Selected Topics in Quantum Electronics 15, 114-119 (2009). [6] L. B. Shaw, B. Cole, P. A. Thielen, J. S. Sanghera, and I. D. Aggarwal, "Mid-wave IR and long-wave IR laser potential of rare-earth doped chalcogenide glass fiber," IEEE Journal of Quantum Electronics 37, 1127-1137 (2001). [7] H. Sakr, D. Furniss, Z. Tang, L. Sojka, N. A. Moneim, E. Barney, S. Sujecki, T. M. Benson, and A. B. Seddon, "Superior photoluminescence (PL) of Pr3+-In, compared to Pr3+-Ga, selenide-chalcogenide bulk glasses and PL of optically-clad fiber," Optics Express 22, 21236-21252 (2014). [8] L. Sojka, Z. Tang, D. Furniss, H. Sakr, A. Oladeji, E. Beres-Pawlik, H. Dantanarayana, E. Faber, A. B. Seddon, T. M. Benson, and S. Sujecki, "Broadband, mid-infrared emission from Pr3+ doped GeAsGaSe chalcogenide fiber, optically clad," Optical Materials 36, 1076-1082 (2014). [9] Z. Tang, D. Furniss, M. Fay, H. Sakr, L. Sojka, N. Neate, N. Weston, S. Sujecki, T. M. Benson, and A. B. Seddon, "Mid-infrared photoluminescence in small-core fiber of praseodymium-ion doped selenide-based chalcogenide glass," Optical Materials Express 5, 870-886 (2015). [10] M. F. Churbanov, I. V. Scripachev, V. S. Shiryaev, V. G. Plotnichenko, S. V. Smetanin, E. B. Kryukova, Y. N. Pyrkov, and B. I. Galagan, "Chalcogenide glasses doped with Tb, Dy and Pr ions," Journal of Non-Crystalline Solids 326, 301-305 (2003). [11] Z. Tang, V. S. Shiryaev, D. Furniss, L. Sojka, S. Sujecki, T. M. Benson, A. B. Seddon, and M. F. Churbanov, "Low loss Ge-As-Se chalcogenide glass fiber, fabricated using extruded preform, for mid-infrared photonics," Optical Materials Express 5, 1722-1737 (2015). [12] G. E. Snopatin, M. F. Churbanov, A. A. Pushkin, V. V. Gerasimenko, E. M. Dianov, and V. G. Plotnichenko, "High purity arsenic-sulfide glasses and fibers with minimum attenuation of 12 dB/km," Optoelectronics and Advanced Materials-Rapid Communications 3, 669-671 (2009). [13] M. Bernier, V. Fortin, N. Caron, M. El-Amraoui, Y. Messaddeq, and R. Vallee, "Mid-infrared chalcogenide glass Raman fiber laser," Optics Letters 38, 127-129 (2013). [14] M. Bernier, V. Fortin, M. El-Amraoui, Y. Messaddeq, and R. Vallee, "3.77 m fiber laser based on cascaded Raman gain in a chalcogenide glass fiber," Optics Letters 39, 2052-2055 (2014). [15] R. Thapa, R. R. Gattass, V. Nguyen, G. Chin, D. Gibson, W. Kim, L. B. Shaw, and J. S. Sanghera, "Low-loss, robust fusion splicing of silica to chalcogenide fiber for integrated mid-infrared laser technology development," Optics letters 40, 5074-5077 (2015). [16] R. S. Quimby, L. B. Shaw, J. S. Sanghera, and I. D. Aggarwal, "Modeling of cascade lasing in Dy : Chalcogenide glass fiber laser with efficient output at 4.5 m," IEEE Photonics Technology Letters 20, 123-125 (2008). [17] L. Sojka, Z. Tang, H. Zhu, E. Beres-Pawlik, D. Furniss, A. B. Seddon, T. M. Benson, and S. Sujecki, "Study of mid-infrared laser action in chalcogenide rare earth doped glass with Dy3+, Pr3+ and Tb3+," Optical Materials Express 2, 1632-1640 (2012). [18] S. Sujecki, L. Sojka, E. Beres-Pawlik, Z. Tang, D. Furniss, A. B. Seddon, and T. M. Benson, "Modelling of a simple Dy3+ doped chalcogenide glass fibre laser for mid-infrared light generation," Optical and Quantum Electronics 42, 69-79 (2010). [19] S. Sujecki, "An Efficient Algorithm for Steady State Analysis of Fibre Lasers Operating under Cascade Pumping Scheme," Intl journal of electronics and telecommunications 60, 143-149 (2014).  

Numerical modeling of lathanide-ion doped fibre lasers operating within mid-infrared wavelength region

Name not available

Nottingham eTheses

Numerical modeling of lathanide-ion doped fibre lasers operating within mid-infrared wavelength region

Abstract

Similar works

Full text

Available Versions

Nottingham ePrints

Name not available

Name not available

Nottingham eTheses