1：Experimental Design and Method Selection:

A multi-rod serial-connection structure is adopted for SBS experiments by comparing K8 glass and fused silica medium at a 10 Hz repetition rate. The optimized structure is obtained according to variation of the pump power density.

2：Sample Selection and Data Sources:

Bulk fused silica is used as the SBS medium. Parameters of fused silica medium are provided in the paper.

3：List of Experimental Equipment and Materials:

Quanta-Ray laser (Spectra-Physics Company) is used as the pumping source. A p-polarized light originating from a Spectra-Physics injection seeded single-longitudinal-mode laser at a fundamental wavelength of 1064 nm and pulse width of 10 ns operating at a repetition rate of 10 Hz, acts as the pump beam source.

4：Experimental Procedures and Operational Workflow:

The pump beam size is reduced from 8 mm to 5.2 mm using a beam reducer comprising 2 lenses L1 and L2 of focal lengths 30 cm and ?20 cm, respectively. The input beam is introduced to the solid rod via a quarter-wave plate (QWP) and lens L

5：2 mm using a beam reducer comprising 2 lenses L1 and L2 of focal lengths 30 cm and ?20 cm, respectively. The input beam is introduced to the solid rod via a quarter-wave plate (QWP) and lens LData Analysis Methods:

3. 5. Data Analysis Methods: The amplified Stokes pulse is separated by a system consisting of PBS1 and QWP, and then divided into 2 beams using a half-wave plate (HWP2) and PBS2. One of these 2 beams is injected into an energy meter or power meter to measure the energy or power, and the other is detected by a photodetector (Thorlabs DET02AFC) of bandwidth 1.2 GHz, rise time 50 ps, fall time 250 ps.