The sensitivities of current gravitational-wave detectors are limited around signal frequencies 100 Hz by mirror thermal noise. One proposed option to reduce this noise is operate the in a higher-order spatial laser mode. This operation would require high-power input beam such Here, we discuss generation Hermite–Gaussian modes HG2,2, HG3,3, and HG4,4 using one water-cooled light modulator (SLM)...