article published R. Driben author B.A. Malomed author 293 department Optimization of the compression of input 𝑁 -solitons into robust ultra-narrow fundamental solitons, with a tunable up- or downshifted frequency, is proposed in photonic crystal fibers free of the Raman effect. Due to the absence of the Raman self-frequency shift, these fundamental solitons continue propagation, maintaining the acquired frequency, once separated from the input 𝑁 soliton’s temporal slot. A universal optimal value of the relative strength of the third-order dispersion is found, providing the strongest compression of the fundamental soliton is found. It depends only on the order of the injected 𝑁 -soliton. The largest compression degree significantly exceeds the analytical prediction supplied by the Satsuma–Yajima formula. The mechanism behind this effect, which remains valid in the presence of the self-steepening, is explained. 2013 eng 10.1364/OL.38.003623 38183623-3626 R. Driben and B. A. Malomed, “Generation of tightly compressed solitons with a tunable frequency shift in Raman-free fibers,” <i>Optics Letters</i>, vol. 38, no. 18, pp. 3623–3626, 2013, doi: <a href="https://doi.org/10.1364/OL.38.003623">10.1364/OL.38.003623</a>. Driben, R., and B.A. Malomed. “Generation of Tightly Compressed Solitons with a Tunable Frequency Shift in Raman-Free Fibers.” <i>Optics Letters</i> 38, no. 18 (2013): 3623–26. <a href="https://doi.org/10.1364/OL.38.003623">https://doi.org/10.1364/OL.38.003623</a>. Driben R, Malomed BA. Generation of tightly compressed solitons with a tunable frequency shift in Raman-free fibers. <i>Optics Letters</i>. 2013;38(18):3623-3626. doi:<a href="https://doi.org/10.1364/OL.38.003623">10.1364/OL.38.003623</a> Driben, R., &#38; Malomed, B. A. (2013). Generation of tightly compressed solitons with a tunable frequency shift in Raman-free fibers. <i>Optics Letters</i>, <i>38</i>(18), 3623–3626. <a href="https://doi.org/10.1364/OL.38.003623">https://doi.org/10.1364/OL.38.003623</a> R. Driben, B.A. Malomed, Optics Letters 38 (2013) 3623–3626. @article{Driben_Malomed_2013, title={Generation of tightly compressed solitons with a tunable frequency shift in Raman-free fibers}, volume={38}, DOI={<a href="https://doi.org/10.1364/OL.38.003623">10.1364/OL.38.003623</a>}, number={18}, journal={Optics Letters}, author={Driben, R. and Malomed, B.A.}, year={2013}, pages={3623–3626} } Driben, R., and B. A. Malomed. “Generation of Tightly Compressed Solitons with a Tunable Frequency Shift in Raman-Free Fibers.” <i>Optics Letters</i>, vol. 38, no. 18, 2013, pp. 3623–26, doi:<a href="https://doi.org/10.1364/OL.38.003623">10.1364/OL.38.003623</a>. 432522023-04-01T21:05:33Z2023-04-01T21:05:36Z