Optical and thermal designs of near field transducer for heat assisted magnetic recording

Abstract

Heat assisted magnetic recording (HAMR) is considered one of the new generation hard drive recording technologies for increasing the data storage density. At its core, HAMR devices are dependent on plasmonic nano antennas, called near field transducers (NFT) to locally deliver heat to storage media. Hence, the design of NFT is crucial for an optimized HAMR device. Several types of NFT designs have been studied through optical and thermal simulations and are quantified using appropriate figures of merit. In addition, the possibility of exciting NFTs at a longer wavelength (1550 nm) has been studied, and it is found that there is a significant improvement of the thermal performance. The effect of having tapers in the geometry of the NFT and their role in improving the NFT thermal performance are also discussed. These studies point to different directions that performance of NFT can be improved.

Relationship between temperature rise and thermal conductivity in a magnetic medium during heated dot magnetic recording

“…The near-field light is generated by a near-field transducer (NFT) using localized surface plasmons. 25) Highanisotropy granular media, such as L10 FePt, are currently being developed for recording media combined with HAMR technology. However, HAMR technology combined with L10 FePt-based bit-patterned media (BPM) is being investigated to expand the performance limit of granular media and to realize ultrahigh data storage densities in hard disk drives.…”

Simulation of Chemical Order–Disorder Transitions Induced Thermally at the Nanoscale for Magnetic Recording and Data Storage

“…In our work, we simulate the relaxation rates for CODTs in Fe x Al 1– x alloys, which can be induced at the nanoscale by compression of thermal energy. One feasible way for such nanopatterning is to use a heated tip of scanning probe microscope. − Also, thermally induced patterning of extreme features (down to ∼50 nm) is achievable by using near-field optical effects − as well as special tools upon that basis, for example, a near-field transducer (NFT) whose design is being developed currently for heat-assisted magnetic recording (HAMR). − We show that a CODT within a nanoscale spot can occur extensively even in the nanosecond regime. To induce this process at moderate temperatures comparable to those necessary for the transformations in established PCMs, the atomic lattice of a CODT alloy should contain a sufficient number of vacancies.…”