Maximum-Likelihood Sequence Detector for Dynamic Mode High Density Probe Storage

TL;DR

This paper presents a maximum likelihood sequence detection method using the Viterbi algorithm for high-density data storage with dynamic mode cantilever probes, significantly improving detection performance over existing schemes.

Contribution

It introduces a novel Viterbi-based maximum likelihood sequence detector tailored for dynamic mode probe storage systems, enhancing data retrieval accuracy.

Findings

Detector outperforms existing schemes by several orders of magnitude

Model effectively captures system memory and inter-symbol interference

Dynamic mode operation reduces wear on probe and media

Abstract

There is an increasing need for high density data storage devices driven by the increased demand of consumer electronics. In this work, we consider a data storage system that operates by encoding information as topographic profiles on a polymer medium. A cantilever probe with a sharp tip (few nm radius) is used to create and sense the presence of topographic profiles, resulting in a density of few Tb per in.2. The prevalent mode of using the cantilever probe is the static mode that is harsh on the probe and the media. In this article, the high quality factor dynamic mode operation, that is less harsh on the media and the probe, is analyzed. The read operation is modeled as a communication channel which incorporates system memory due to inter-symbol interference and the cantilever state. We demonstrate an appropriate level of abstraction of this complex nanoscale system that obviates the need for an involved physical model. Next, a solution to the maximum likelihood sequence detection problem based on the Viterbi algorithm is devised. Experimental and simulation results demonstrate that the performance of this detector is several orders of magnitude better than the performance of other existing schemes.