The Scaling Capability of Heat Assisted Magnetic Recording

Abstract

In this study, we analyze the scaling potential of heat-assisted magnetic recording (HAMR) and the factors ostensibly preventing scaling. In principle, as each length in the problem scales by a factor of <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$1/x$ </tex-math></inline-formula> , we would expect the areal density (AD) of the system to scale as <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${x}^{2}$ </tex-math></inline-formula> . To underpin the 20% CAGR expectation in the ASRC roadmap, we present a numerical investigation of HAMR where we consider the scaling of grain density, thermal spot size, reader dimensions, media velocity, and other factors. We also evaluate the relative importance of these scaling factors and assess the effect of <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${K}_{u}{V}{/}{kT}$ </tex-math></inline-formula> on writing. The results show that reader, grain density, and thermal spot scaling are more critical in realistic HAMR systems. Finally, we highlight the importance of improving the reader by varying the width and the head electronic signal-to-noise ratio (HESNR).