Konishi Mitsutaka, Santo Hisashi, Hongo Yuki, Tajima Kazuyuki, Hosoi Masaharu, Saiki Toshiharu
Graduate School of Science and Technology, Keio University, Hiyoshi, Kohoku,Yokohama, Kanagawa 223-8522, Japan.
Appl Opt. 2010 Jun 20;49(18):3470-3. doi: 10.1364/AO.49.003470.
We demonstrate amorphization in a Ge(10)Sb(2)Te(13) (GST) thin film through a nonthermal process by femtosecond electronic excitation. Amorphous recording marks were formed by irradiation with a single femtosecond pulse, and were confirmed to be recrystallized by laser thermal annealing. Scanning electron microscope observations revealed that amorphization occurred below the melting temperature. We performed femtosecond pump-probe measurements to investigate the amorphization dynamics of a GST thin film. We found that the reflectivity dropped abruptly within 500fs after excitation by a single pulse and that a small change in the reflectivity occurred within 5ps of this drop.
我们通过飞秒电子激发的非热过程在Ge(10)Sb(2)Te(13)（GST）薄膜中实现了非晶化。用单个飞秒脉冲辐照形成了非晶记录标记，并通过激光热退火证实其发生了再结晶。扫描电子显微镜观察表明，非晶化发生在熔点温度以下。我们进行了飞秒泵浦-探测测量以研究GST薄膜的非晶化动力学。我们发现，在单个脉冲激发后500飞秒内反射率急剧下降，并且在该下降的5皮秒内反射率发生了小的变化。
