【摘要】 高能量超短脉冲在强场超快研究中具有不可或缺的应用价值。飞秒激光脉冲后压缩技术由于色散管理元件的有限反射带宽和非线性吸收的限制，在近单周期脉宽压缩和能量阈值方面存在瓶颈。飞秒激光脉冲自压缩技术通过在非线性介质中特殊构建负色散环境，自动补偿自相位调制（SPM）引入的正色散，同步实现光谱展宽与脉冲压缩。历经十余年的发展，脉冲自压缩技术已经取得了太瓦（TW）级亚周期自压缩脉宽、波长可调谐共振色散波（RDW）的研究成果，在高能量超短光源、紫外（UV）泵浦非线性光学、高次谐波产生（HHG）等领域展现出广阔前景。首先阐述时间孤子脉冲自压缩的产生原理，继而综述其在微结构空芯光纤、空芯毛细管（HCF）、固体薄片（MPC）、多通盒及空间脉冲自压缩的研究现状，最后探讨该技术当前面临的挑战与未来发展方向。更多还原

【Abstract】 Significance Energetic ultrashort laser pulses hold significant value in strong-field ultrafast research, such as attosecond science and petahertz electronics. Femtosecond laser pulse post-compression techniques encountered bottlenecks due to the limited reflection bandwidth and nonlinear absorption limitations of dispersion management components. Femtosecond laser pulse self-compression utilizes specially engineered negative dispersion environments, automatically compensate for the positive dispersion induced by self-phase modulation(SPM), broadening the spectrum while simultaneously achieving pulse compression. This approach eliminates the usage of dispersion management components like chirped mirrors in post-compression, avoiding their limitations on spectral broadening and energy scaling. Pulse self-compression theoretically enables the generation of single-cycle or even sub-cycle pulses across different spectral bands. Depending on the underlying mechanism, self-compression can be categorized into temporal soliton, filamentation and conical emission, with temporal soliton self-compression being the primary form. Pulse self-compression technology holds significant value in energetic ultrashort laser source, ultraviolet(UV)-pumped nonlinear optics, and high-harmonic generation(HHG).Progress Soliton is a localized wave packet formed by the balance between nonlinearity and dispersion, maintaining its shape during propagation. Mollenauer et al. first experimentally observed soliton propagation. Photonic bandgap fibers(PBF) utilize a periodic thinlayer structure to create photonic bandgaps within specific spectral bands, confining light to the core and satisfying the dispersion-loss balance conditions required for soliton dynamics. Researchers have observed phenomena like soliton self-compression and Raman soliton self-frequency shift in PBF. However, their limited bandwidth and large dispersion slope severely constrain applications requiring extreme spectral broadening and pulse compression. Anti-resonant hollow-core fibers employ a different light-guiding mechanism than PBF, overcoming the inherent bandwidth and dispersion slope limitations of the latter. By employing sub-micron cladding designs and gas pressure modulation, they enable flexible control over dispersion and nonlinearity. This achieved self-compressed pulse widths down to the single-cycle level(Fig. 8) and generated wavelength-tunable resonant dispersive waves(RDW)(Fig. 15). Nevertheless, the complex micro-structures of both types of fiber lead to relatively low damage thresholds, limiting the energy scalability of pulse self-compression in micro-structured hollow-core fibers.Hollow-capillary fibers(HCF), characterized by the absence of intricate micro-structures, represent a distinct class of optical waveguides. Their primary advantage lies in their significantly higher energy threshold, which is fundamentally governed by two key factors: the ionization threshold of the gas filling the core and the core diameter itself. This inherent simplicity facilitates superior energy handling compared to micro-structured fibers. A landmark advancement occurred in 2019 when Travers et al. introduced a novel soliton self-compression scheme within HCF, specifically designed for few-cycle pulse pumping. Their innovative approach employed a cascaded design that strategically combined elements of post-compression with the intrinsic self-compression dynamics occurring within the HCF itself(as depicted in Fig. 2 and Fig. 10). This technique yielded remarkable results in a 3 m long HCF: the generation of an 800 nm, 1.2 fs self-compressed soliton pulse. This corresponds to an astonishingly ultrashort transient electric field width of 412 as, representing the shortest pulse duration via any pulse compression technique. Demonstrating the versatility and scalability of the method, Travers’ team further extended this technique to the 1800-nm spectral band in 2020. Crucially, this extension was achieved without requiring complex front-end pre-compression stages, directly producing 2 fs self-compressed pulses(Fig. 11). Recently, we extended HCF-based self-compressed soliton to the blue(400 nm) spectral band(Fig. 12), achieving 4.4 fs clean self-compressed blue pulses and exceptional temporal-spatial quality, with much higher energy and energy scalability than blue soliton generation in micro-structured hollow core fibers. As another hallmark product of self-compression, RDW exhibits wavelength tunability across the ultraviolet(UV)-visible spectrum(Fig. 17) and significantly higher UV generation efficiency than HHG. Researchers have conducted a series of studies on their generation mechanisms(Fig. 16 and Fig. 18) and applications.Multiplate continuum(MPC) generation serves as another typical medium for post-compression. However, their dispersion characteristics depend solely on the inherent properties of the medium and are difficult to flexibly control like in gas-filled hollow-core fibers. Consequently, soliton self-compression in MPC has been limited to long-wavelength bands. In 2024, Chen et al. proposed a novel mechanism for self-compressing ultrahigh-peak-power pulses in normally dispersive media based on fifth-order nonlinear effects. This scheme modulates the fifth-order nonlinear susceptibility under ultrahigh peak power, inducing significant negative dispersion within the normally dispersive medium to effectively counteract the material’s positive dispersion, theoretically driving near-infrared soliton self-compression(Fig. 24) in MPC scheme.Beyond temporal soliton-based self-compression, certain spatial optical phenomena can also drive pulse self-compression. Filamentation occurs when the pulse peak power exceeds the critical power for self-focusing in the medium. The plasma generated by ionization provides negative dispersion, compensating for the positive dispersion introduced by SPM. This technique faces challenges like spatial-spectral inhomogeneity. Researchers have proposed improved methods such as conical emission self-compression for optimization(Fig. 27).Conclusions and Prospects Pulse self-compression stands as the sole technique currently capable of generating high-energy pulses with sub-cycle durations, holding significant application value in strong-field ultrafast research. Nevertheless, this technology faces challenges including energy thresholds, limitations on the minimum achievable self-compressed soliton pulse width, and the underlying physics of RDW. Future prospects for expansion exist in broadening the operational spectral bands, exploring higher soliton orders and dimensionality, optimizing front-end optical systems, and advancing integration and consolidation approaches.更多还原