  Simultaneously transmitting and reflecting reconfigurable intelligent surface
(STAR-RIS) is a cutting-edge concept for the sixth-generation (6G) wireless
networks. In this paper, we propose a novel system that incorporates STAR-RIS
with simultaneous wireless information and power transfer (SWIPT) using rate
splitting multiple access (RSMA). The proposed system facilitates communication
from a multi-antenna base station (BS) to single-antenna users in a downlink
transmission. The BS concurrently sends energy and information signals to
multiple energy harvesting receivers (EHRs) and information data receivers
(IDRs) with the support of a deployed STAR-RIS. Furthermore, an optimization is
introduced to strike a balance between users' sum rate and the total harvested
energy. To achieve this, an optimization problem is formulated to optimize the
energy/information beamforming vectors at the BS, the phase shifts at the
STAR-RIS, and the common message rate. Subsequently, we employ a meta deep
deterministic policy gradient (Meta-DDPG) approach to solve the complex
problem. Simulation results validate that the proposed algorithm significantly
enhances both data rate and harvested energy in comparison to conventional
DDPG.
