A study of Ta2O5 photonic crystals waveguide for Heat-Assisted Magnetic Recording (HAMR).

The research and development of the light delivery system for Heat-Assisted Magnetic Recording (HAMR), which lowers optical transmitted loss, is still in the spotlight and keeps going. Since the commercial product of hard disk drive (HDD) with HAMR technology has been launched, the important part of HAMR technology, which is optical light delivery or waveguide, still needs to be developed. This paper proposes the study of tantalum pentoxide (Ta₂O₅) photonic crystal (PhC) waveguide for the HAMR light delivery system. The Ta₂O₅ PhC waveguides are designed at a 1,360 nm wavelength, which is simply to find a light source such as a diode laser. The PhC waveguide dimensions were calculated following the photonic bandgap (PBG) theory. The Ta₂O₅ PhC waveguides were fabricated and tested. The transmitted efficiency and waveguide attenuation loss of the PhC waveguide is studied and compared with the reference waveguide, which is a dielectric waveguide. The transmitted efficiency (%) of Ta₂O₅ PhC and dielectric waveguides are 87.3% and 87.2%, respectively. The waveguide attenuation loss (dB/mm) of the Ta₂O₅ PhC and the dielectric waveguide are 0.73 and 4.42 dB/mm, respectively. The waveguide attenuation loss can be described by the physical properties of the material used and waveguide structure design. From the experiment results, the optical transmitted efficiency of the Ta₂O₅ PhC waveguide is greater than 85%, which is acceptable optical performance. The attenuation loss of the Ta₂O₅ PhC waveguide is better than the dielectric waveguide considering it is a suitable material used and its waveguide structure design. It is also concluded that the Ta₂O₅ PhC waveguide is promising as the candidate for light delivery waveguide for HAMR. [ABSTRACT FROM AUTHOR]