单盘35TB！ IBM富士创磁带存储新纪录

IBM瑞士苏黎世实验室日前就宣布，他们和日本富士(Fujifilm)公司合作，创造了磁带领域的存储密度新纪录。

　　IBM展示的这款磁带样品存储密度达到每平方英寸29.5Gb，是目前常见的39倍。由此技术支撑的磁带每卷存储容量可达35TB，是目前IBM LTO第四代磁带的44倍。

　 　为实现这一突破，研究人员们应用了多项新技术。首先是由富士胶片提供的NANOCUBIC磁带，使用钡铁氧体作为磁介质提高存储密度。接下来是IBM苏 黎世实验室开发的磁头精确定位技术，将磁带上的磁道数提高了25倍。新的信号处理算法降低读写噪声，将线性存储密度提升50%。再加上巨磁阻技术的应用， 终于达成了如今的创纪录存储密度。

Or:

The scientists at IBM Research - Zurich, in cooperation with the FUJIFILM Corporation of Japan, recorded data onto an advanced prototype tape, at a density of 29.5 billion bits per square inch - about 39 times the areal data density of today's most popular industry-standard magnetic tape product*. To achieve this feat, IBM Research has developed several new critical technologies, and for the past three years worked closely with FUJIFILM to optimize its next-generation dual-coat magnetic tape based on barium ferrite (BaFe) particles. 

"This exciting achievement shows that tape storage is alive and strong and will continue to provide users reliable data protection, while maintaining a cost advantage over other storage technologies, including hard disk drives and flash," said Cindy Grossman, vice president, IBM Tape and Archive Storage Systems. 

These new technologies are estimated to enable cartridge capacities that could hold up to 35 trillion bytes (terabytes) of uncompressed data**. This is about 44 times*** the capacity of today's IBM LTO Generation 4 cartridge. A capacity of 35 terabytes of data is sufficient to store the text of 35 million books, which would require 248 miles (399 km) of bookshelves.

See

转载所乃至的4点技术细节

Technical details: IBM's world-record achievement leverages notable improvements in four areas of the magnetic tape system

1. New high-density, dual-coated particulate magnetic tape: Developed by FUJIFILM Corporation in Japan in close collaboration with IBM Research scientists, this next-generation version of its NANOCUBIC™ tape uses a new ultra-fine, perpendicularly-oriented barium-ferrite magnetic medium that enables high-density data recording without using expensive metal sputtering or evaporation coating methods. 
2. Advanced servo control technologies for ultra accurate head positioning: Three new servo control technologies have been developed by IBM Research - Zurich, leading to a more than 25-fold increase in the number of data tracks that can be squeezed onto the half-inch-wide tape: 1) a new servo pattern, enabling the generation of high-bandwidth nanometer-scale position information; 2) a new method for detecting and decoding the position information encoded in the servo pattern, and 3) advanced state-space-based control concepts that, combined with the other two technologies, culminated in the demonstration of an extremely precise track-follow performance of less than 24 nm standard deviation from the target track position. These technologies were instrumental in reducing the track width to less than 0.45 micrometers. 
3. Innovative signal-processing algorithms for the data channel: An advanced data read channel based on a new data-dependent noise-predictive, maximum-likelihood (DD-NPML) detection scheme was developed at IBM Research - Zurich to enable the accurate detection of the data despite the reduction in the signal-to-noise ratio resulting from the use of an ultra-narrow 0.2- um data reader head. With this technique, which also takes the noise characteristics of FUJIFILM's BaFe medium into account, a linear density increase of more than 50 percent relative to LTO Generation 4 was achieved. 
4. Low-friction GMR (giant magnetoresistive) read/write head assemblies: Two new head technologies have been developed by the tape development and research teams at IBM Research - Almaden, namely, a new reduced-friction head assembly that allows the use of smoother magnetic tapes and an advanced GMR head module incorporating optimized servo readers. These head technologies were critical for achieving the required track-follow performance mentioned above.