Optimal write head design for perpendicular magnetic recording

Herein, we adopt an approach to search for the optimal solution of the write head design based on the maximization of the signal-to-noise ratio (SNR) and the minimization of the bit error rate (BER) via micromagnetic simulations the grain-flipping probability (GFP) model and channel simulation . We select six variables as the design parameters in the write head. An initial screen testing is performed to decide the nominal values of these parameters and their variations. The design of experiments (DOE) is conducted by applying an orthogonal array (OA) and LLG-based micromagnetic simulations are carried out to obtain the magnetization distributions in the recording media for each head design. These magnetization distributions are then used to train the corresponding grain-flipped probability model (GFPs). The SNRs and BERs are obtained from processing the GFP model output with a software channel. The Taguchi method is used to identify the optimal solution by maximizing the SNRs and minimizing the BERs. Using the Taguchi method, we predict the SNR and the BER at the optimal head design and finally, the verification is performed by micromagnetic simulation, GFP model, SNR characterization and BER calculation for the optimal design.