Ultra-fast and ultra-high density magnetic recording applying localized circularly polarized near-field light generated by plasmon antenna

针对利用光致磁化反转现象的超快超高密度磁记录，我们研究了1）建立将圆偏振光限制在纳米量级的方法，2）澄清表面等离子体共振的瞬态响应，以及3）验证超快超高密度记录。结果表明，利用四叶三叶草光阑和孤立粒子介质，证实了孤立粒子介质中存在受限的小圆偏振光。结果表明，圆偏振光能够从表面等离子体激元产生，其在金属和电介质材料之间的界面处传播。瞬态响应分析表明，圆偏振光在约50 fs内出射。利用等离子体天线产生的光学近场，用90 fs脉冲激光写入62 × 67 nm ~ 2的微小磁记录标记。

For an ultra-fast and ultra-high density magnetic recording using a photo-induced magnetization reversal phenomenon, we studied 1) establishing a method of confining circularly polarized light into an order of nano-meter size, 2) clarifying transient response of surface plasmon resonance, and 3) verifying an ultra-fast and ultra-high density recording. As a result, a confined small circularly polarized light in an isolated particle medium was confirmed by using both a four-leaf clover aperture and an isolated particle medium. It was shown that the circularly polarized light was able to be generated from surface plasmon polaritons, which propagated at an interface between a metal and a dielectric material. It is found that the circularly polarized light was exited in ~50 fs by a transient response analysis. A tiny magnetic recording mark of 62 x 67 nm2 were written by optical near field generated by a plasmon antenna using a 90-fs pulsed laser.