As the areal density of commercial hard disk drives is quickly approaching the terabit per square inch milestone, the need to further decrease the head-medium spacing (HMS) is becoming ever more critical, as it is a necessary enabler to good writability as well as strong read-back signal integrity. It is estimated that the HMS will soon need to cross the 6-7 nm mark in order to reach this density point. It is remarkable to realize that the error rate of the stored digital signal that is being read back will improve by about 2x for every 0.3 nanometer of decreased HMS. In addition to relentless demand for novel, ultrathin protecting films of overcoat and lubricant, and subnanometer air gap between the disk and the head, alternative recording technologies presently being contemplated involve heating the disk to over 500°C (heat-assisted magnetic recording or HAMR) and/or physically isolating magnetic bits on small islands of sub-30 nm in physical dimensions (bit-patterned recording or BPR).

We invite investigators to contribute original research articles as well as review articles that will stimulate the continuing efforts to understand the physical limits to ultralow HMS, the development of novel lubricant and overcoat films, and the fine control of subnanometer head-disk clearance. We are particularly interested in articles with fundamental insight into the tribology and chemistry of the head-disk interface under HAMR or BPR conditions.

Potential topics include, but are not limited to:

• Recent developments in thin lubricant and overcoat films and characterization of their physical and chemical properties under thermal transients
• Lubricant and overcoat modeling, both in the continuum approximation, as well as molecular dynamics
• Nanoactuation technology for magnetic spacing control, slider touch-down detection, and disk clearance control
• Air-bearing modeling and thermomechanical effects on heads and media under HAMR conditions and experimental validation
• BPR interface: air-bearing modeling, experiments, and planarization technologies
• Role of disk drive environment (humidity, temperature, particulate, and organic contaminants) in head-disk interface reliability
• Head and disk corrosion mechanisms and control