Understanding the effect of the tape surface on the metal-particle tape medium noise

Spacing fluctuations resulting from the head-tape interface dominate the metal-particle tape medium noise. Utilizing narrow-gap record heads, the spatial correlation of the head-medium interface has been completely and accurately characterized using a magnetic recording measurement. The measurements show that the spacing fluctuations damp with shorter wavelength, or in other words, the tape head-medium noise possesses a long spatial correlation length. In addition, the results demonstrate that the roughness-induced spacing fluctuations originate from portions of the tape surface that contact the tape, i.e., the load-bearing surface. This understanding of the head-medium noise reveals that the majority of the tape medium noise occurs during the recording process, and not during signal playback. Spatial correlation measurements on low-density (5 kfci) recordings provide verification of these conclusions. The study offers a thorough understanding of the surface roughness role on producing the head-medium noise. (C) 2002 American Institute of Physics.