Write-Once Disc with BiFeO Thin Films for Multilevel Optical Recording

We found out that small marks are formed without large deformation and intersymbol interference (ISI) on a BiFeO thin film. Therefore, a BiFeO write-once disk is suitable for multilevel optical recording. We confirmed that our write-once disk realizes a recording capacity of 23 GB using a laser diode with a 405 nm wavelength and a 0.65 numerical aperture objective lens.