The 23 references with contexts in paper A. Rudenkov S., V. Kisel E., A. Yasukevich S., K. Hovhannesyan L., A. Petrosyan G., N. Kuleshov V., А. Руденков С., В. Кисель Э., А. Ясюкевич С., К. Ованесьян Л., А. Петросян Г., Н. Кулешов В. (2018) “Регенеративный усилитель чирпированных фемтосекундных импульсов на основе кристалла Yb:CALYO для спектроскопии возбуждения-зондирования с высоким временным разрешением // Yb:CALYO-based femtosecond chirped pulse regenerative amplifier for temporally resolved pump-probe spectroscopy” / spz:neicon:pimi:y:2018:i:3:p:205-214

1
Breitling D., Föhl C., Dausinger F., Kononenko T., Konov V. Ultrashort Interaction with Materials. Femtosecond Technology for Technical and Medical Applications. F. Dausinger, F. Lichtner, H. Lubatschowski, eds. Springer, Berlin, 2004. doi: 10.1007/b96440
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  1. In-text reference with the coordinate start=8322
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    Introduction Diode-pumped femtosecond laser sources with pulse repetition frequencies (PRF) of hundreds of kilohertz and pulse energies of tens microjoules are of practical importance for high temporal and spectral resolution measurements, precision micromachining, optical memory and biomedicine
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    [1]
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    . Extremely high average output powers up to the kilowatt level could be obtained by means of direct amplification of high repetition-rate oscillators. 1.1 kW of average power at 20 MHz repetition rate with 615 fs pulses were obtained using the Innoslab Yb:YAG concept [2]. 830 W trains of 640 fs pulses at 78 MHz were demonstrated by employing largemode area Yb-doped fiber

2
Russbueldt P., Mans T., Weitenberg J., Hoffmann H.D., Poprawe R. Compact diode-pumped 1.1 kW Yb:YAG Innoslab femtosecond amplifier. Opt. Lett., 2010, vol. 35, рр. 4169–4171. doi: 10.1364/OL.35.004169
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  1. In-text reference with the coordinate start=8613
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    Extremely high average output powers up to the kilowatt level could be obtained by means of direct amplification of high repetition-rate oscillators. 1.1 kW of average power at 20 MHz repetition rate with 615 fs pulses were obtained using the Innoslab Yb:YAG concept
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    [2]
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    . 830 W trains of 640 fs pulses at 78 MHz were demonstrated by employing largemode area Yb-doped fiber amplifiers [3]. Pulses at lower repetition frequencies, up to a few megahertz, with substantially higher energy and peak power are preferred for many applications.

3
Eidam Tino, Hanf Stefan, Seise Enrico, V. Andersen Thomas, Gabler Thomas, Wirth Christian, Schreiber Thomas, Limpert Jens, Tünnermann Andreas. Femtosecond fiber CPA system emitting 830 W average output power. Opt. Lett., 2010, vol. 35, pp. 94–96. https:// doi.org/10.1364/OL.35.000094
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  1. In-text reference with the coordinate start=8731
    Prefix
    high average output powers up to the kilowatt level could be obtained by means of direct amplification of high repetition-rate oscillators. 1.1 kW of average power at 20 MHz repetition rate with 615 fs pulses were obtained using the Innoslab Yb:YAG concept [2]. 830 W trains of 640 fs pulses at 78 MHz were demonstrated by employing largemode area Yb-doped fiber amplifiers
    Exact
    [3]
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    . Pulses at lower repetition frequencies, up to a few megahertz, with substantially higher energy and peak power are preferred for many applications. These pulse trains can be generated conveniently with solid-state diodepumped regenerative amplifiers (RAs).

4
Fleischhaker R., Gebs R., Budnicki A., Wolf M., Kleinbauer J., Sutter D.H. Compact gigawatt-class sub-picosecond Yb:YAG thin-disk regenerative chirped-pulse amplifier with high average power at up to 800 kHz. 2013 Conference on Lasers and ElectroOptics – International Quantum Electronics Conference (Optical Society of America, 2013), paper CFIE_4_1. https:// doi.org/10.1109/CLEOE-IQEC.2013.6801054
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  1. In-text reference with the coordinate start=9187
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    These pulse trains can be generated conveniently with solid-state diodepumped regenerative amplifiers (RAs). Up to now, the highest average power RA systems are presented by thin-disk concept RAs. For example, up to 160 W average output power at 800 kHz PRF with 750 fs pulse duration were achieved in
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    [4]
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    . Up to 100 W average power at 400 kHz PRF with 800 fs pulse duration were reached in [5] employing Yb:YAG thin-disk active element. Despite thin-disk based regenerative amplifier systems demonstrate high average power, it should be noted that pulse duration of such systems is not less than 700 fs. 295 fs pulses were demonstrated for thin disk RA system that ap

5
Schneider W., Ryabov A., Lombosi Cs., Metzger T., Major Zs., Fülöp J.A., Baum P. 800-fs, 330 μJ pulses from a 100-W regenerative Yb:YAG thin-disk amplifier at 300 kHz and THz generation in LiNbO3. Opt. Lett., 2014, vol. 39, pp. 6604–6607. https://doi.org/10.1364/OL.39.006604.
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  1. In-text reference with the coordinate start=9287
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    For example, up to 160 W average output power at 800 kHz PRF with 750 fs pulse duration were achieved in [4]. Up to 100 W average power at 400 kHz PRF with 800 fs pulse duration were reached in
    Exact
    [5]
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    employing Yb:YAG thin-disk active element. Despite thin-disk based regenerative amplifier systems demonstrate high average power, it should be noted that pulse duration of such systems is not less than 700 fs. 295 fs pulses were demonstrated for thin disk RA system that applied nonlinear pulse amplification regime but with substantially reduced output power (36 W) [6

6
Pouysegur J., Delaigue M., Honninger C., Zaouter Y., Georges P., Druon F., Mottay E. Numerical and Experimental Analysis of Nonlinear Regenerative Amplifiers Overcoming the Gain Bandwidth Limitation. Selected Topics in Quantum Electronics, IEEE Journal of, 2015, vol. 21, no. 1, pp. 212, 219. https:// doi.org/10.1109/JSTQE.2014.2321520
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  1. In-text reference with the coordinate start=9681
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    Despite thin-disk based regenerative amplifier systems demonstrate high average power, it should be noted that pulse duration of such systems is not less than 700 fs. 295 fs pulses were demonstrated for thin disk RA system that applied nonlinear pulse amplification regime but with substantially reduced output power (36 W)
    Exact
    [6]
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    . Another approach to implementation of RA systems is based on bulk regenerative amplifiers. The highest output power reported so far for bulk RAs is 42 W at 500 kHz pulse repetition frequency obtained in RA based on the active medium with high thermooptical properties – Yb:Lu2O3 [7].

7
Caracciolo E., Pirzio F., Kemnitzer M., Gorjan M., Guandalini A., Kienle F., Agnesi A., Aus Der Au J. 42 W femtosecond Yb:Lu2O3 regenerative amplifier. Opt. Lett., 2016, vol. 41, pp. 3395–3398. https:// doi.org/10.1364/OL.41.003395
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  1. In-text reference with the coordinate start=9965
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    Another approach to implementation of RA systems is based on bulk regenerative amplifiers. The highest output power reported so far for bulk RAs is 42 W at 500 kHz pulse repetition frequency obtained in RA based on the active medium with high thermooptical properties – Yb:Lu2O3
    Exact
    [7]
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    . Relatively long amplified pulses of about 780 fs pulse duration obtained due to narrow gain bandwidth of Yb:Lu2O3. Substantially reduced pulse duration of 217 fs with relatively high output power of 28 W demonstrated at 500 kHz in RA based on crystal with wide gain bandwidth – Yb:CALGO [8].

8
Caracciolo E., Kemnitzer M., Guandalini A., Pirzio F., Aus der Au J., Agnesi A. 28-W, 217 fs solid-state Yb:CAlGdO4 regenerative amplifiers. Opt. Lett., 2013, vol. 38, pp. 4131–4133. https:// doi.org/10.1364/OL.38.004131.
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  1. In-text reference with the coordinate start=10264
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    Relatively long amplified pulses of about 780 fs pulse duration obtained due to narrow gain bandwidth of Yb:Lu2O3. Substantially reduced pulse duration of 217 fs with relatively high output power of 28 W demonstrated at 500 kHz in RA based on crystal with wide gain bandwidth – Yb:CALGO
    Exact
    [8]
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    . But the usage of active medium with wide gain bandwidth is not a sufficient condition for obtaining short amplified pulse duration due to the strong gain narrowing effect [9] that reduce amplified pulse spectral width and increase minimal transform-limited pulse duration.

9
Raybaut P., Balembois F., Druon F., Georges P. Numerical and experimental study of gain narrowing in ytterbium-based regenerative amplifiers. IEEE Journal of Quantum Electronics, 2005, vol. 41, no. 3, pp. 415– 425. doi: 10.1109/JQE.2004.841930
Total in-text references: 1
  1. In-text reference with the coordinate start=10452
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    Substantially reduced pulse duration of 217 fs with relatively high output power of 28 W demonstrated at 500 kHz in RA based on crystal with wide gain bandwidth – Yb:CALGO [8]. But the usage of active medium with wide gain bandwidth is not a sufficient condition for obtaining short amplified pulse duration due to the strong gain narrowing effect
    Exact
    [9]
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    that reduce amplified pulse spectral width and increase minimal transform-limited pulse duration. Several methods for overcoming the negative contribution of gain narrowing effect have been proposed [10, 11].

10
Kim G.H., Yang J., Chizhov S.A., Sall E.G., Kulik A.V., Yashin V.E., Kang U. A high brightness Q-switched oscillator and regenerative amplifier based on a dual-crystal Yb:KGW laser. Laser Phys. Lett., 2013, vol. 10, 125004 (5 p.). https://doi.org/10.1088/1612-2011/10/12/125004
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  1. In-text reference with the coordinate start=10669
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    usage of active medium with wide gain bandwidth is not a sufficient condition for obtaining short amplified pulse duration due to the strong gain narrowing effect [9] that reduce amplified pulse spectral width and increase minimal transform-limited pulse duration. Several methods for overcoming the negative contribution of gain narrowing effect have been proposed
    Exact
    [10, 11]
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    . The output power of about 21 W at 200 kHz PRF with 200 fs pulse duration is obtained with Yb:KGW dual crystal system [10]. Femtosecond laser pulses with duration as short as 97 fs with output power of 1.2 W at 50 kHz PRF were obtained with the Yb:CALGO RA system which demonstrates the possibility of sub-100 fs pulses amplification [11].

  2. In-text reference with the coordinate start=10796
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    Several methods for overcoming the negative contribution of gain narrowing effect have been proposed [10, 11]. The output power of about 21 W at 200 kHz PRF with 200 fs pulse duration is obtained with Yb:KGW dual crystal system
    Exact
    [10]
    Suffix
    . Femtosecond laser pulses with duration as short as 97 fs with output power of 1.2 W at 50 kHz PRF were obtained with the Yb:CALGO RA system which demonstrates the possibility of sub-100 fs pulses amplification [11].

11
Pouysegur Julien, Delaigue Martin, Zaouter Yoann, Hönninger Clemens, Mottay Eric, Jaffrès Anaël, Loiseau Pascal, Viana Bruno, Georges Patrick, Druon Frédéric. Sub-100-fs Yb:CALGO nonlinear regenerative amplifier. Opt. Lett., 2013, vol. 38, pp. 5180–5183. https:// doi.org/10.1364/OL.38.005180
Total in-text references: 2
  1. In-text reference with the coordinate start=10669
    Prefix
    usage of active medium with wide gain bandwidth is not a sufficient condition for obtaining short amplified pulse duration due to the strong gain narrowing effect [9] that reduce amplified pulse spectral width and increase minimal transform-limited pulse duration. Several methods for overcoming the negative contribution of gain narrowing effect have been proposed
    Exact
    [10, 11]
    Suffix
    . The output power of about 21 W at 200 kHz PRF with 200 fs pulse duration is obtained with Yb:KGW dual crystal system [10]. Femtosecond laser pulses with duration as short as 97 fs with output power of 1.2 W at 50 kHz PRF were obtained with the Yb:CALGO RA system which demonstrates the possibility of sub-100 fs pulses amplification [11].

  2. In-text reference with the coordinate start=11016
    Prefix
    Femtosecond laser pulses with duration as short as 97 fs with output power of 1.2 W at 50 kHz PRF were obtained with the Yb:CALGO RA system which demonstrates the possibility of sub-100 fs pulses amplification
    Exact
    [11]
    Suffix
    . Despite the availability of femtosecond lasers providing wide spectral width pulses [12–14] based on Yb seed lasers a large number of RA systems described in the literature have narrower pulse spectral width not over than 15 nm.

12
Pirzio Federico, Cafiso D. Di Dio Samuele, Kemnitzer Matthias, Guandalini Annalisa, Kienle Florian, Veronesi Stefano, Tonelli Mauro, Aus der Au Juerg, Agnesi Antonio. Sub-50-fs widely tunable Yb:CaYAlO4 laser pumped by 400-mW single-mode fiber-coupled laser diode. Opt. Express, 2015, vol. 23, pp. 9790–9795. https:// doi.org/10.1364/OE.23.009790
Total in-text references: 1
  1. In-text reference with the coordinate start=11115
    Prefix
    Femtosecond laser pulses with duration as short as 97 fs with output power of 1.2 W at 50 kHz PRF were obtained with the Yb:CALGO RA system which demonstrates the possibility of sub-100 fs pulses amplification [11]. Despite the availability of femtosecond lasers providing wide spectral width pulses
    Exact
    [12–14]
    Suffix
    based on Yb seed lasers a large number of RA systems described in the literature have narrower pulse spectral width not over than 15 nm. And this also limits the amplified pulse spectral width and compressed pulse duration.

13
Gao Ziye, Zhu Jiangfeng, Wang Junli, Wei Zhiyi, Xu Xiaodong, Zheng Lihe, Su Liangbi, Xu Jun. Generation of 33 fs pulses directly from a Kerr-lens mode-locked Yb:CaYAlO4 laser. Photon. Res., 2015, vol. 3, pp. 335– 338. https:// doi.org/10.1364/PRJ.3.000335
Total in-text references: 1
  1. In-text reference with the coordinate start=11115
    Prefix
    Femtosecond laser pulses with duration as short as 97 fs with output power of 1.2 W at 50 kHz PRF were obtained with the Yb:CALGO RA system which demonstrates the possibility of sub-100 fs pulses amplification [11]. Despite the availability of femtosecond lasers providing wide spectral width pulses
    Exact
    [12–14]
    Suffix
    based on Yb seed lasers a large number of RA systems described in the literature have narrower pulse spectral width not over than 15 nm. And this also limits the amplified pulse spectral width and compressed pulse duration.

14
Ma Jie, Huang Haitao, Ning Kaijie, Xu Xiaodong, Xie Guoqiang, Qian Liejia, Ping Loh Kian, Tang Dingyuan. Generation of 30 fs pulses from a diode-pumped graphene mode-locked Yb:CaYAlO4 laser. Opt. Lett., 2016, vol. 41, pp. 890–893. https:// doi.org/10.1364/OL.41.000890
Total in-text references: 1
  1. In-text reference with the coordinate start=11115
    Prefix
    Femtosecond laser pulses with duration as short as 97 fs with output power of 1.2 W at 50 kHz PRF were obtained with the Yb:CALGO RA system which demonstrates the possibility of sub-100 fs pulses amplification [11]. Despite the availability of femtosecond lasers providing wide spectral width pulses
    Exact
    [12–14]
    Suffix
    based on Yb seed lasers a large number of RA systems described in the literature have narrower pulse spectral width not over than 15 nm. And this also limits the amplified pulse spectral width and compressed pulse duration.

15
Kaminskii A.A., Petrosyan A.G., Ovanesyan K.L., Shirinyan G.O., Butaeva T.I., Markosyan A.A. Two generation channels of the CaYAlO4 disordered crystal. Inorganic Materials, 1991, vol. 27, pp. 426–427. 213
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  1. In-text reference with the coordinate start=11743
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    Crystal growth Single crystals of Yb3+:CaYAlO4 (tetragonal structure, space group D174h-I4/mmm) doped with Yb3+(1.4 at. % and 3.5 at. %) were grown from stoichiometric melts by Czochralski method
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    [15]
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    . Yb3+ ions occupy Y3+ sites of the lattice with 9-fold coordination. Crystallization was carried out under an enclosed argon atmosphere using iridium crucibles (50 × 50 × 30 mm3) and seed crystals oriented along [110].

16
Sumida D.S., Fan T.Y. Effect of radiation trapping on fluorescence lifetime and emission cross section measurements in solid-state laser media. Opt. Lett., 1994, vol. 19, pp. 1343–1345. https:// doi.org/10.1364/OL.19.001343
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  1. In-text reference with the coordinate start=12985
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    Radiative lifetime was estimated by using crystalline powder immersed in glycerine suspension in order to eliminate radiation trapping effect caused by significant overlap of the absorption and emission bands
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    [16, 17]
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    . Measured lifetime for different weight content 207 208 of Yb3+(1.4 at. %):CaYAlO4 and Yb3+(3.5 at. %): CaYAlO4 crystalline powder in glycerine suspension are shown in Figure 2. Measured kinetics of luminescence decay for Yb3+:CaYAlO4 with 1.4 at. % and 3.5 at. % concentrations are shown in Figure 3.

17
Kühn Henning, Fredrich-Thornton Susanne T., Kränkel Christian, Peters Rigo, Petermann Klaus. Model for the calculation of radiation trapping and description of the pinhole method. Opt. Lett., 2007, vol. 32, pp. 1908– 1910. https:// doi.org/10.1364/OL.32.001908
Total in-text references: 1
  1. In-text reference with the coordinate start=12985
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    Radiative lifetime was estimated by using crystalline powder immersed in glycerine suspension in order to eliminate radiation trapping effect caused by significant overlap of the absorption and emission bands
    Exact
    [16, 17]
    Suffix
    . Measured lifetime for different weight content 207 208 of Yb3+(1.4 at. %):CaYAlO4 and Yb3+(3.5 at. %): CaYAlO4 crystalline powder in glycerine suspension are shown in Figure 2. Measured kinetics of luminescence decay for Yb3+:CaYAlO4 with 1.4 at. % and 3.5 at. % concentrations are shown in Figure 3.

18
Yasyukevich A.S., Shcherbitskii V.G., Kisel V.E., Mandrik A.V., Kuleshov N.V. Integral method of reciprocity in the spectroscopy of laser crystals with impurity centers. Journal of Applied Spectroscopy, 2004, vol. 71, no. 2, pp. 202– 208. https:// doi.org/10.1023/B:JAPS.0000032875.04400.a0.
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  1. In-text reference with the coordinate start=13705
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    The radiative lifetime of the 2F5/2 manifold of Yb3+ions in CaYAlO4 was estimated to be (430 ± 15) μs. The stimulated emission cross sections (Figure 1) were calculated by use of integral reciprocity method
    Exact
    [18]
    Suffix
    . Figure 1 – Absorption and stimulated emission crosssection spectra of the Yb3+:CaYAlO4 Figure 2 – Measured lifetime for different weight content of Yb3+:CaYAlO4 crystalline powder in glycerine suspension Figure 3 – Kinetics of luminescence decay 2F5/2 manifold of Yb3+-ions in CaYAlO4 The Yb3+:CaYAlO4 crystal exhibits broad stimulated emission cross-section spectra in

19
Li Dongzhen, Xu Xiaodong, Zhu Haomiao, Chen Xueyuan, Tan Wei De, Zhang Jian, Tang Dingyuan, Ma Jan, Wu Feng, Xia Changtai, Xu Jun. Characterization of laser crystal Yb:CaYAlO4. J. Opt. Soc. Am. B 28, 2011, pp. 1650–1654. https:// doi.org/10.1364/JOSAB.28.001650
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  1. In-text reference with the coordinate start=14472
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    The stimulated emission cross-section for σ-polarization demonstrates higher value of about ≈ 0.7·10-20 cm2 at 1030–1040 nm in comparison with ≈ 0.5·10-20 cm2 for π-polarization. Obtained spectroscopic properties of the Yb3+:CaYAlO4 crystal demonstrate good agreement with described in literature data
    Exact
    [19]
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    . Experimental setup The conceptual scheme of the system layout is shown in Figure 4. Figure 4 – Experimental setup of broad-band seeded Yb3+:CaYAlO4 chirped pulse RA Приборы и методы измерений 2018.

20
Kisel V.E., Rudenkov A.S., Pavlyuk A.A., Kovalyov A.A., Preobrazhenskii V.V., Putyato M.A., Rubtsova N.N., Semyagin B.R., Kuleshov N.V. Highpower, efficient, semiconductor saturable absorber modelocked Yb:KGW bulk laser. Opt. Lett., 2015, vol. 40, pp. 2707–2710. https:// doi.org/10.1364/OL.40.002707
Total in-text references: 1
  1. In-text reference with the coordinate start=15814
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    The RA setup chosen for this experiment is quite common, employing a 40-mm-long double-BaB2O4 Pockels cell for pulse injection and ejection. Pulse repetition frequency (PRF) was chosen to be 200 kHz to prevent damage of the optical elements. «Off-axes» pump layout was used for longitudinal pumping of the active element
    Exact
    [20–22]
    Suffix
    . Main advantage of such a pump scheme is that all the cavity mirrors have highly reflecting coating at (900–1100) nm. Maximum pump power was 25 W. 2mm-long a-cut Yb3+(3.5 at. %): CaYAlO4 crystal was used as a gain medium.

21
Rudenkov Alexander, Kisel Viktor, Matrosov Vladimir, Kuleshov Nikolai. 200 kHz 5.5 W Yb3+:YVO4-based chirped-pulse regenerative amplifier. Opt. Lett., 2015, vol. 40, pp. 3352–3355. https:// doi.org/10.1364/OL.40.003352.
Total in-text references: 1
  1. In-text reference with the coordinate start=15814
    Prefix
    The RA setup chosen for this experiment is quite common, employing a 40-mm-long double-BaB2O4 Pockels cell for pulse injection and ejection. Pulse repetition frequency (PRF) was chosen to be 200 kHz to prevent damage of the optical elements. «Off-axes» pump layout was used for longitudinal pumping of the active element
    Exact
    [20–22]
    Suffix
    . Main advantage of such a pump scheme is that all the cavity mirrors have highly reflecting coating at (900–1100) nm. Maximum pump power was 25 W. 2mm-long a-cut Yb3+(3.5 at. %): CaYAlO4 crystal was used as a gain medium.

22
Rudenkov Alexander, Kisel Viktor, Yasukevich Anatol, Hovhannesyan Karine, Petrosyan Ashot, Kuleshov Nikolay. Yb3+:LuAlO3 crystal as a gain medium for efficient broadband chirped pulse regenerative amplification. Opt. Lett., 2017, vol. 42, pp. 2415–2418. https:// doi.org/10.1364/OL.42.002415
Total in-text references: 1
  1. In-text reference with the coordinate start=15814
    Prefix
    The RA setup chosen for this experiment is quite common, employing a 40-mm-long double-BaB2O4 Pockels cell for pulse injection and ejection. Pulse repetition frequency (PRF) was chosen to be 200 kHz to prevent damage of the optical elements. «Off-axes» pump layout was used for longitudinal pumping of the active element
    Exact
    [20–22]
    Suffix
    . Main advantage of such a pump scheme is that all the cavity mirrors have highly reflecting coating at (900–1100) nm. Maximum pump power was 25 W. 2mm-long a-cut Yb3+(3.5 at. %): CaYAlO4 crystal was used as a gain medium.

23
Agrawal G.P. Nonlinear Fiber Optics (Fourth Edition). Optics and Photonics, Academic Press, San Diego, 2006, p. 529. https://doi.org/10.1016/B978-0-12-369516-1.X5000-6. 214
Total in-text references: 1
  1. In-text reference with the coordinate start=21955
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    Mathematical modelling To estimate the amplified pulse spectra limited mostly by gain crystal characteristics and gain narrowing effect mathematical simulation was made 211 b a b a with constant level of intracavity losses (≈ 5 %) for wide spectral range covering active crystal gain bandwidth. Simulation was based on the split-step Fourier method
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    [23]
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    . Gain curve was calculated by means of the absorption (ABS) and stimulated emission (SE) cross-section spectra under a certain population of the upper laser manifold of Yb3+ ions which corresponds to our experimental conditions.