High-power narrow linewidth single-frequency lasers have attracted extensive interest due to their superior characteristics in some fields, such as gravitational wave detection[1], quantum information optics[2], atomic physics[3] and nonlinear frequency conversion[4–6]. The most widely used approaches to obtain high-power narrow linewidth lasers are master oscillator power amplification (MOPA) structures based on low-power narrow linewidth seeds[7,8] and single-cavity structures with direct high-power output[9,10]. However, in MOPA systems, aside from the problems of beam quality deterioration and mode instability due to thermal accumulation[11], the linewidth broadening introduced by spontaneous radiation during the amplification process cannot be ignored. Using a single cavity to obtain a high-power single-frequency laser overcomes the complexity of laser structures but faces the problem that the linewidth cannot be further narrowed due to strong pumping intensity noise[9]. In addition, the output wavelength in the above-mentioned solutions is critically dependent on the energy level structure of the gain medium, which limits the applicability of conventional high-power single-frequency lasers in some special wavelength laser applications (e.g., sodium-guided star research)[12]. The emergence of optical nonlinear frequency conversion techniques accompanies the development of high-power laser technology to provide a new perspective for achieving high-power narrow linewidth laser radiation at specific wavelengths. Of these, stimulated Brillouin scattering (SBS), a third-order nonlinear effect, offers excellent advantages in applications of realizing ultra-narrow linewidth lasers[13–15], microwave photonics[16–18] and optical storage[19]. The heavy attenuation mechanism of acoustic phonons combined with the strong feedback provided by the cavity enables micro-waveguide Brillouin lasers (BLs) to produce laser outputs far below the linewidth of conventional single-frequency lasers and close to the quantum noise limit[20,21]. Similarly, strong linewidth narrowing has been reported in fiber BLs[22] and laser outputs of sub-kHz magnitude subject to technical noise[23]. These demonstrations based on waveguide structures also face some insurmountable problems in power boosting. The high Q cavity achieves a narrow linewidth with a concomitant lowering of the threshold of the higher-order Stokes frequency component, resulting in a limited single-frequency BL power scale[24]. The phase-matching condition of high-order Stokes light can be broken using inter-mode scattering through a tailored cavity structure[25], but the thermal effects accumulated in the cavity at power scaling detune the phase-matching condition of the single-frequency BL, leading to power-clamping phenomena[20]. The mechanism of Stokes linewidth compression in fiber BLs relies on the employment of long fiber cavities[26], whereas their phase-matching conditions require a free spectral range (FSR) comparable to the Brillouin gain linewidth, which thereby limits further linewidth compression and power boosting. Increasing the pump power in anticipation of achieving a single-frequency power increase will inevitably produce spontaneous radiation of higher-order Stokes frequency components[22,27].