[16a-D704-1~10] 10.3 Spin devices, magnetic memories and storages

▲ [16a-D704-10] Magnetic field response characteristics of anomalous Hall magnetic recording reader

〇(PC)Prabhanjan Dilip Kulkarni¹, Tomoya Nakatani¹, Hitoshi Iwasaki¹, Hirofumi Suto¹, Yuya Sakuraba¹ (1.NIMS)

Keywords:anomalous Hall effect, magnetic read head, symmetric response

The recent progress in energy assisted magnetic recording technologies are pushing the areal recoding density of hard disk drives (HDDs) to beyond 2 Tbit/in². Consequently, the size of HDD read head sensor (reader) must shrink to obtain the required resolution. The physical size of the reader for 4 Tbit/in² is predicted to be 17 nm in shield gap (G) and 9 nm in reader width (W). However, achieving G < 20 nm using the present tunnel magnetoresistance (TMR) based reader is a challenging task owing to its multilayered structure. We had proposed a new reader structure using anomalous Hall effect (AHE), which consists of only one layer of AHE material. Here, we present finite element simulation studies of the AHE reader and compare the results with the conventional TMR reader. While the output voltage of TMR readers is asymetric with respect to the magnetic field, the output voltage of AHE reader shows a perfect symmetry. The symmetric output curve of AHE readers enables us to increase the sensor utilization, thus higher SNR can be obtained. Therefore, AHE sensor is an attractive candidate for the readers for beyond 2 Tbit/in².