[OPTICAL REVIEW Vol. 14, No. 4 (2007) 236-242]
© 2007 The Optical Society of Japan

Investigation of Near-Field Imaging Characteristics of Radial Polarization for Application to Optical Data Storage

Wan-Chin KIM, No-Cheol PARK*, Yong-Joong YOON, Hyun CHOI, and Young-Pil PARK

Center for Information Storage Devices, Yonsei University, 134 Shinchon-Dong, Sudaemoon-Ku, Seoul 120-749, Korea

(Received January 31, 2007; Accepted April 5, 2007)

Radially polarized incident light can generate a more confined longitudinal electric field on a focal plane in near-field (NF) optics than focusing circularly polarized light. Using this phenomenon, it is feasible to reduce beam spot size on storage media to increase the areal density of optical data storage. A radially polarized beam generates a beam spot which is 20% more confined on the 1st surface of medium than that of circularly polarized light. However, the peak intensity of total electric field sharply decreases and its transverse component is much more dominant inside the media stack. This confirms that radially polarized optics can be a candidate not for an NF recording system but for an NF read-only memory (ROM) system. Potentially, the results could be useful to understand the effect of radial and circular polarizations inside and outside medium for various applications of NF optics.

Key words: radially polarized light, solid immersion lens (SIL), circularly polarized light, near-field recording (NFR), read-only memory (ROM), phase change (PC) media

*E-mail address: pnch@yonsei.ac.kr