1：Experimental Design and Method Selection:

The study focuses on a four-terminal tandem design combining LPC-Si bottom cells and perovskite top cells. Optical simulations using GenPro4 (a MATLAB-based ray optics model) are performed to estimate current generation potential and identify loss mechanisms. Experimental methods include attaching optical filters (cutoff and perovskite) to LPC-Si cells to simulate tandem conditions.

2：Sample Selection and Data Sources:

LPC-Si solar cells are produced on Corning Eagle XG glass substrates with specific layer stacks. Perovskite filters and cells are fabricated on ITO-coated glass substrates. Data sources include I-V measurements, EQE measurements, and absorption spectra from reflection/transmission data.

3：List of Experimental Equipment and Materials:

Equipment includes sun simulator (Wacom WXS-156S-L2), EQE setup (self-built), spectrophotometer (PerkinElmer LAMBDA 1050), atomic force microscope (Park Systems XE70), ellipsometer (SENTECH SE850), PECVD system, electron beam evaporator, CW-diode laser (DILAS IS42), spin-coater, thermal evaporator, atomic layer deposition system, sputtering system. Materials include Corning Eagle XG glass, silicon oxide/nitride/oxynitride layers, nanocrystalline silicon, amorphous silicon, perovskite materials (Cs0.05(MA0.17FA0.83)Pb1.1(I0.83Br0.17)3), PTAA, C60, SnO2, ITO, IZO, LiF, cutoff filter (Newport FSQ-RG780), index matching liquid (Norland LOT181).

4：05(MA17FA83)Pb1(I83Br17)3), PTAA, C60, SnO2, ITO, IZO, LiF, cutoff filter (Newport FSQ-RG780), index matching liquid (Norland LOT181). Experimental Procedures and Operational Workflow:

4. Experimental Procedures and Operational Workflow: LPC-Si cell preparation involves deposition of barrier/passivation layers, absorber layer, doping layer, capping layer, laser crystallization, hydrogen passivation, and IBC contact formation. Perovskite filter/cell preparation involves layer deposition (ITO, PTAA, perovskite, C60, SnO2, IZO, LiF) via spin-coating, evaporation, ALD, and sputtering. Characterization includes I-V measurements under AM1.5 spectrum, EQE measurements, and absorption measurements. Filters are attached to LPC-Si cells mechanically, and measurements are conducted with and without filters.

5：5 spectrum, EQE measurements, and absorption measurements. Filters are attached to LPC-Si cells mechanically, and measurements are conducted with and without filters. Data Analysis Methods:

5. Data Analysis Methods: Optical simulations with GenPro4 are used to fit measured absorption data and calculate current losses. VOC reduction under filtered light is analyzed using the ideal solar cell equation. Statistical analysis of cell parameters (mean and standard deviation) is performed.