Spatial self-phase modulation (SSPM), i.e. the formation, temporal evolution and subsequent distortion of self-diffraction ring patterns, generated by transmitting a continuous wave 532nm laser beam through solutions containing C₆₀ or C₇₀ has been investigated. The nonlinear optical response regarding SSPM of such systems was studied, to our knowledge for the first time, in dependence of various solvents, different sample temperatures and viscosities. The SSPM patterns consisted of a number of concentric rings, generated due to induced refractive index changes and start with a central spot, expanding into a series of concentric rings. The number of rings increases steadily and the ring pattern becomes larger with time until a maximum is reached. Thereafter, thermal convection leads to a distortion of the upper part of the ring system, while the lower part keeps its shape. The dependence of temporal and spatial evolution of self-diffraction ring pattern on different sample parameters and not only the functional material itself, leading to our conclusion that thermal effects are responsible for the observed SSPM. For further substantiation, measurements of C₆₀ in toluene at a wavelength of 1070nm have been carried out. At this wavelength no absorption occurs and no SSPM patterns were observed. Knowing that for ultashort pulses no significant thermal effects take place, we performed additional measurements at a pulse length of 8ps and a wavelength of 527nm. Also in this case no SSPM patterns were generated. In order to gain a deeper understanding of the involved physical processes, we developed a thermal blooming simulation: Thermally-induced refractive index changes and convection caused by locally heating of the solution by the laser beam were taken into account, any other nonlinear phenomena were left aside. A laser beam propagating through an absorbing solution generates similar ring structures under these conditions, what is in fully agreement with our experimental results. Additionally, as a practical application of SSPM a laser protection device is presented.

空间自相位调制 (SSPM)，即自衍射环图案的形成、时间演变和随后的畸变，通过将连续波 532nm 激光束传输通过含有 C ₆₀或 C _{70 的}溶液产生已被调查。据我们所知，第一次研究了关于此类系统的 SSPM 的非线性光学响应，这取决于各种溶剂、不同的样品温度和粘度。SSPM 图案由许多同心环组成，由于诱导折射率变化而产生，并从中心点开始，扩展为一系列同心环。环的数量稳步增加，并且环模式随着时间的推移变得更大，直到达到最大值。此后，热对流导致环系统上部变形，而下部保持其形状。自衍射环图案的时空演化对不同样品参数的依赖性，而不仅仅是功能材料本身，导致我们的结论是热效应是造成观察到的 SSPM 的原因。为了进一步证实，C的测量₆₀在 1070nm 波长的甲苯中进行了实验。在该波长下没有吸收发生，也没有观察到 SSPM 模式。知道对于超短脉冲不会发生显着的热效应，我们在 8ps 的脉冲长度和 527nm 的波长下进行了额外的测量。同样在这种情况下，没有生成 SSPM 模式。为了更深入地了解所涉及的物理过程，我们开发了热晕染模拟：考虑了由激光束局部加热溶液引起的热致折射率变化和对流，并保留了任何其他非线性现象在旁边。在这些条件下，通过吸收溶液传播的激光束会产生类似的环结构，这与我们的实验结果完全一致。此外，