Perfect soliton crystals in Kerr cavities with negative pure-quartic dispersion

Pure-quartic cavity solitons are an emerging class of dissipative Kerr solitons that are promising for various applications including telecommunications. They form in passive cavities under the balance of negative quartic dispersions and Kerr nonlinearity, as well as loss and parametric gain. Using a generalized Lugiato Lefever equation, we numerically investigate dynamics of pure-quartic cavity solitons. We observe the spontaneous emergence of uniformly spaced solitons, perfect soliton crystals (PSC), out of temporal chaos. These perfect crystals break into soliton molecules as detuning is increased. We use a strain analogy to quantify the stability of these PSCs and behaviour of temporal patterns in the soliton existence regime. Our results interpret such behaviours, could be closely linked with the enhanced soliton-soliton interactions, mediated via oscillatory tails of pure quartic solitons.