Surface-plasmon resonance of a planar lollipop near-field transducer

Surface-plasmon resonance of a lollipop near-field transducer integrated in a planar solid immersion mirror for heat-assisted magnetic recording has been studied by pump-probe photothermal measurement and recording on a phase-change medium. Lollipops of 190 nm in disk diameter and 20-nm-thick were found to exhibit two resonant modes in 710-950 nm. Recording on a phase-change medium showed that the wavelength at the short resonant mode is not sensitive to the presence of a medium, while the resonance at the long wavelength exhibits significant redshift. On resonance, the plasmon efficiency enables the pronounced near-field optical recording.