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ALT'23 The 30th International Conference on Advanced Laser Technologies
LS-O-14
Spectroscopic properties of Cr2+ ions in Zm-xMnxSe solid solutions
M.E. Doroshenko1, H. Jelinkova2, A. Riha2, K. Pierpoint1
1- Prokhorov General Physics Institute of the Russian Academy of Sciences, Vavilov Street 38, Moscow Russia 2- Czech Technical University in Prague, Brehova 7, Prague, Czech Republic
Main author email address: kmartynova19@gmail.com
Over the last few decades, the development of ZnSe:Cr2+ tunable lasers that find a wide range of practical applications has made great progress. Maximum powers in excess of 140 W and efficiencies up to 60%, as well as the generation of ultrashort pulses (43 fs), have recently been demonstrated [1].The benefits ofCr2+ ions in AnBVI materials (such as ZnS, CdSe, CdMnTe, e.t.c. [2-4]) include very broad absorption and emission spectra with a high cross-section, negligible excited-state absorption, and a relatively long lifetime that is only mildly dependent on temperature. The interest in the search for new AIIBVI matrices and their solid solutions doped with Cr2+is associated with the possibility to modify the chromium ions properties, thereby covering other spectral ranges. This work aims to investigate the Cr2+ ions spectroscopic properties in a range of cubic Zn;-xMnxSe (x = 0-0.4) solid solutions.
The absorption and fluorescence spectra were measured at room temperature for a wide range of Zn;_ xMnxSe:Cr2+ (x = 0-0.4) samples. It was shown that with an increase in Mn content x, the maxima of both absorption and fluorescence spectra move practically linearly toward lower energies at a rate of roughly 30 cm-1 for every 10% of Mn (see Fig. 1 for example). This shift is likely caused by the decrease in crystal field strength in Zn;-xMnxSe solid solution with x due to the higher value of the lattice parameter and the lower position of the upper 5E Cr2+ ion level.
The temperature dependence of Cr2+ ions decay time was measured over a broad temperature range. Examples of the resulting curves for three samples with Mn content x = 0.05, 0.3, and 0.4 are presented in Fig. 2. As can be seen, the decay rate of Cr2+ ions is almost independent of temperature for all samples up to about 240 K. The decrease in decay time with temperature starts earlier for samples with higher Mn content. The value of the AEa gap between the bottom of the Cr2+ ion 5E configuration curve and the intersection of the 5T2 and 5E curves was estimated, and the observed temperature dependence was associated with a AEa gap decrease with Mn content (x) increase, resulting in stronger non-radiative quenching of Cr2+ ion fluorescence.
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Fig. 1. Cr2+ ions absorption line maxima position (circles) and lattice constant a (squares) in Znl-xMnxSe crystal for various Mn content (x).
Zn, „Mn^SeiCr21
s m s» SS =0.4 \f\ •
......m\
......i x=03 ^-O
...... ....... N
150 200 250 300 350 400 Temperature, K
Fig. 2. Temperature dependence of Cr2+ ions fluorescence decay time in Zni_xMnxSe crystal for different Mn content x.
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This work was supported by Russian Science Foundation Project № 23-22-00236.
[1]S. B. Mirov et al. Frontiers of Mid-IR Lasers Based on Transition Metal Doped Chalcogenides, IEEE Journal of Selected Topics in Quantum Electronics, vol. 24 (5), 1601829, (2018).
[2] L.D. DeLoach, R.H. Page, G.D.Wilke, S.A. Payne, and W.F.Krupke, Transition metal-doped zinc chalcogenides: spectroscopy and laser demonstration of a new class of gain media, IEEE Journal of Quantum Electronics, vol. 32 (6), pp. 885-895, (1996).
[3] V.I. Kozlovsky, Y.V. Korostelin, Y.P. Podmar'kov, Y.K. Skasyrsky, M.P. Frolov, Middle infrared Fe2+:ZnS, Fe2+:ZnSe and Cr2+:CdSe lasers: new results, Journal of Physics: Conference Series, vol. 740, 012006,(2016).
[4] M.E. Doroshenko, V.V. Osiko, H. Jelinkova, M. Jelinek, M. Nemec, J. Sulc, N.O. Kovalenko, A.S. Gerasimenko, V.M. Puzikov, Spectroscopic and laser properties of Cr2+ ions in Zn^MgxSe solid solutions, Optical Materials, vol. 47, pp. 185-189, (2015).