System-level requirements for heat-assisted magnetic recording at high areal density are presented in this article. The primary factors that affect bit error rate (BER) are spatial, or media, signal-to-noise ratio (SNR), reader SNR, and channel bit density (CBD). Spatial SNR is largely determined by the interaction between the writer properties and the media properties. For example, how well the thermal gradient matches the grain size. Spatial SNR also depends on how well the reader cross-track resolution matches the track pitch, and the quality of the written pattern. For any given level of spatial SNR, there exists a combination of CBD and reader SNR that results in the desired level of performance. This article elucidates some of the tradeoffs that may be needed to maintain BER as areal density increases, for different bit aspect ratio scenarios. For very high areal density, we show that the geometrical requirements are extremely aggressive, which will most likely require significant invention in head and drive architecture design.

中文翻译：

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热辅助磁记录的几何比例极限

本文介绍了在高面密度下热辅助磁记录的系统级要求。影响误码率（BER）的主要因素是空间或媒体，信噪比（SNR），阅读器SNR和通道位密度（CBD）。空间信噪比在很大程度上取决于写入器属性和媒体属性之间的相互作用。例如，热梯度与晶粒尺寸的匹配程度。空间信噪比还取决于阅读器跨磁道分辨率与磁道间距匹配的良好程度以及所写图案的质量。对于任何给定的空间SNR级别，都存在CBD和读取器SNR的组合，从而产生了所需的性能级别。本文阐明了随着面密度增加而维持BER可能需要的一些权衡，适用于不同的位长宽比方案。对于非常高的面密度，我们证明了几何要求非常苛刻，这很可能需要在磁头和驱动器架构设计中进行重大的发明。