An ultrahigh density optical disk head which utilizes evanescent light (near-field light) had been designed to enhance the near-field optical wave for the throughput increment using the surface plasmon polariton resonance effect between the light inside the near-field optical head and nano-fabricated corrugated metal thin film. The theoretical analysis is discussed with the emphasis on the two- and three-dimensional simulation using finite difference time domain method. It is also experimentally shown that the near-field light enhancement in a waveguide of a clad covered with corrugated gold thin film was observed and that the near-field light enhancement in a waveguide without the film was not. If the corrugation pitch and the focused laser wavelength used with self-aligned microlens are designed properly, more than 20% throughput will be realized using nanometer fabricated metallic grating.
Bibliographical noteFunding Information:
Manuscript received September 21, 2004. This work was supported in part by the Japan Society for the Promotion of Science under Grant-in-Aid for Scientific Research 16560037. K. Goto is with Tokai University, Shizuoka 410-0395, Japan (e-mail: firstname.lastname@example.org). T. Ono is with Tohoku University, Sendai 980-8579, Japan (e-mail: email@example.com). Y.-J. Kim is with Yonsei University, Seoul 120-749, Korea (e-mail: firstname.lastname@example.org). Digital Object Identifier 10.1109/TMAG.2004.842031 Fig. 1. Cross-sectional view of the new near-field optical head structure, which consists of 2-D VCSEL, micro-lens (10 m ) that is covered with corrugated metallic film, and 30 nm aperture array.
All Science Journal Classification (ASJC) codes
- Electronic, Optical and Magnetic Materials
- Electrical and Electronic Engineering