Thermal cross-erase issues in high-data-density phase-change recording

We report on the numerical simulations of high-data-density phase-change re cording (DVR-blue and DVR-red) in order to analyse the phenomenon of therma l cross-erase in land/groove recording. In particular, if a maximum data ca pacity is pursued, which involves a small radial track pitch, thermal cross interference may become an important issue. The question of whether or not the temperature distributions and the related thermal cross-erase probabil ity scale with the optical spot size is addressed. Two different thermal mo dels (a planar model and a land/groove model) were used in which laser heat ing was simulated. Reliable temperature predictions and related trend analy ses require a proper model and accurate input parameters. The thermal condu ctivity of the different layers in the stack was obtained from measurements performed with a time-resolved static tester setup in combination with a n ovel melt-threshold method. Since thermal cross-erase is dependent on the t emporal temperature distribution in the stack, we analysed the most importa nt parameters that possibly contribute to a reduction of the temperature, a nd thus the cross-erase probability, in the adjacent track.