To solve the physical layer security problem of maximizing the secrecy rate, our contributions in this paper can be summarized as follows:  
* We propose a secrecy communication system assisted by RHS. Specifically, we integrate the RHS into the base station (BS) to enhance the system's beamforming accuracy and introduce artificial noise, a commonly used technique in the domain of physical layer security, to improve the overall secrecy rate. The system is designed to operate in the presence of multiple eavesdroppers and a legitimate user. To address this challenge, we propose a hybrid beamforming scheme that jointly optimizes the digital beamforming at the BS and the holographic beamforming at the RHS. * We formulate a secrecy rate maximization problem subject to the transmit power of the base station and the normalized radiation amplitude of the holographic surface. This problem is difficult to solve because it is an optimization problem in which the objective function is non-convex and the optimization variables are coupled. However, it is relatively easy to optimize one optimization variable while the other optimization variable is fixed, so we propose an algorithm of an alternate solution. We decompose the problem into two subproblems: the digital beamforming at the base station and the holographic beamforming at the holographic surface. By alternately solving the two subproblems, convergence will be achieved in the end to maximize the secrecy rate. * Based on simulation results, it is demonstrated that the holographic surface presents promising potential for applications in the field of physical layer security. The simulations have verified the impact of transmission power, eavesdropper quantity, and antenna size on its performance. Additionally, a comparison with an equivalent-sized RIS has been conducted. The simulation results reveal that the holographic surface outperforms the RIS in terms of secrecy of the communication system. The remainder of this paper is organized as follows. The holographic rules and the hardware construction of the holographic surface are presented in Section 2. We present our scenario and system model for our secrecy communication system in Section 3. In Section 4, we pose the problem of optimizing the secrecy rate and provide a detailed description of the algorithm used to solve it. To verify the algorithm's viability and the holographic surface's functionality in the secrecy communication system, we simulate the system model in Section 5. Ultimately, our conclusions are presented in Section 6. Notations: \(j=\sqrt{-1}\) is the imaginary unit, and \((\cdot)^{*}\) denotes the conjugate. \(|\cdot|\) represents the modulus of a complex number, while \(Re(. )\) represents the real part of a complex number. \(\mathcal{CN}\big{(}\mu,\sigma^{2}\big{)}\) denotes the distribution of a circularly symmetric complex Gaussian random variable with mean \(\mu\) and variance \(\sigma^{2}\). \(Tr(M)\) denotes the trace of the square matrix \(M\), while \(M\succeq 0\) denotes it to be positive semi-definite. \(rank(\mathbf{V})\) denotes the rank of any general matrix \(\mathbf{V}\), and \(diag(\mathbf{V})\) represents the diagonalization. \(\mathbb{C}^{Y\times X}\) denotes the space of \(Y\times X\) complex-valued matrices. Figure 1: RHS-aided secrecy communication system.