Chung, M Chung, KM Lee, TS Cheong, BK Kim, WM Song, KB Kim, YD Kim, SG 2024-01-21T14:03:45Z 2024-01-21T14:03:45Z 2021-09-05 2000-06 0021-4922 https://pubs.kist.re.kr/handle/201004/141361 We have analyzed the read-out signal obtained from a phase-change optical disc. The marks were recorded both on land tracks and in groove tracks with the focused laser beam of a wavelength of 685nm and a numerical aperture (NA) of 0.6 Characteristics of the read-out signal of marks recorded both on land tracks and in groove tracks were understood by considering the land/groove configuration of the substrate, the reflectance difference and the phase difference between amorphous and crystalline states of a recording layer. By comparing the measured carrier levels obtained from the land and groove tracks with the simulation results based on the diffraction theory, we found that the measured carrier level difference between land and groove recordings resulted mainly from the effects of groove geometry and the phase difference which was estimated to be 20 degrees for our sample disc. For this work, the groove geometry of the substrate and mark sizes were precisely estimated from transmission electron microscopy (TEM) micrographs. English JAPAN J APPLIED PHYSICS DENSITY Analysis of read-out signals in land/groove recording of a phase-change optical disc Article 10.1143/JJAP.39.3453 1 JAPANESE JOURNAL OF APPLIED PHYSICS PART 1-REGULAR PAPERS SHORT NOTES & REVIEW PAPERS, v.39, no.6A, pp.3453 - 3457 JAPANESE JOURNAL OF APPLIED PHYSICS PART 1-REGULAR PAPERS SHORT NOTES & REVIEW PAPERS 39 6A 3453 3457 scie scopus 000088392800037 2-s2.0-0034204760 Physics, Applied Physics Article DENSITY read-out signal phase-change optical disc land/groove recording Ge2Sb2Te5 carrier level phase difference