Multidimensional solitary states (MDSS)—self-sustained wavepackets—have attracted renewed interest in many different fields of physics. They are of particular importance in nonlinear optics, especially for the nonlinear propagation of ultrashort pulses in multimode fibres, which contain rich spatiotemporal intermodal interactions and dynamics, albeit often in an unstable manner. Here, we report the observation of the formation of highly stable multidimensional solitary states in a molecular gas-filled large-core hollow-core fibre. We experimentally and numerically demonstrate the creation of MDSS by multimillijoule, subpicosecond near-infrared pulses and the underlying physics. We find that the MDSS have a broadband redshifted spectra with an uncommon negative quadratic spectral phase at the output of the hollow-core fibre, originating from Raman enhancement due to the strong intermodal nonlinear interactions. The spatial and temporal localization of MDSS enables the compression of the broadened pulses at the output to 10.8 fs by simple linear propagation in a piece of fused silica. The high spatiotemporal quality of MDSS is further verified by high-harmonic generation. Our results present new opportunities for studying multimodal spatiotemporal dynamics in the high-energy regime. This work also presents a route toward a new class of compact, tunable and high-energy spatiotemporally engineered coherent light sources based on picosecond ytterbium technology.

多维孤立状态（MDSS）（自持波包）在许多不同的物理领域引起了新的兴趣。它们在非线性光学中尤其重要，特别是对于多模光纤中的超短脉冲的非线性传播，这种多模光纤通常以不稳定的方式包含丰富的时空联运相互作用和动力学。在这里，我们报告在分子气体填充大芯空心纤维中形成高度稳定的多维孤立状态的观察。我们在实验和数值上证明了由毫焦耳，亚皮秒近红外脉冲和潜在的物理学原理所产生的MDSS。我们发现MDSS在空心光纤的输出处具有宽带的红移光谱，具有不常见的负二次光谱相位，源于拉曼增强，这是由于强烈的联运非线性相互作用。MDSS的时空定位通过在一块熔融石英中进行简单的线性传播，可以将输出处的加宽脉冲压缩到10.8 fs。高次谐波的产生进一步证实了MDSS的高时空质量。我们的结果为研究高能态下的多峰时空动力学提供了新的机会。这项工作还为基于皮秒y技术的新型紧凑，可调和高能时空工程相干光源的开发提出了一条途径。在一块熔融石英中通过简单的线性传播可达到8 fs。高次谐波的产生进一步证实了MDSS的高时空质量。我们的结果为研究高能态下的多峰时空动力学提供了新的机会。这项工作还为基于皮秒y技术的新型紧凑，可调和高能时空工程相干光源的开发提出了一条途径。在一块熔融石英中通过简单的线性传播可达到8 fs。高次谐波的产生进一步证实了MDSS的高时空质量。我们的结果为研究高能态下的多峰时空动力学提供了新的机会。这项工作还为基于皮秒y技术的新型紧凑，可调和高能时空工程相干光源的开发提出了一条途径。