2022年第83回応用物理学会秋季学術講演会

講演情報

一般セッション(口頭講演)

10 スピントロニクス・マグネティクス » 10.2 スピン基盤技術・萌芽的デバイス技術

[22p-A205-1~18] 10.2 スピン基盤技術・萌芽的デバイス技術

2022年9月22日(木) 13:30 〜 18:30 A205 (A205)

金井 駿(東北大)、笠原 健司(福岡大)、伊藤 啓太(東北大)

17:45 〜 18:00

[22p-A205-16] Observation of persistent coherence in Y3Fe5O12

Takahiko Makiuchi1、Tomosato Hioki2,1、Hiroki Shimizu1、Koujiro Hoshi1,3、Mehrdad Elyasi2、Kei Yamamoto4、Naoto Yokoi1,3、Gerrit E. W. Bauer2、Eiji Saitoh1,2,3,4 (1.Dept. Appl. Phys., UTokyo、2.AIMR, Tohoku Univ.、3.Beyond AI, UTokyo、4.JAEA)

キーワード:magnetization dynamics, spintronics, coherence

Precessional motion of magnetization around a magnetic field decays and reaches the equilibrium. It has been believed that all the information of magnetization phase coherence is lost after the damping. Here we study the phase coherence in a disk-shaped yttrium iron garnet (YIG) by using a microwave pump-and-probe method in which we obtain a measure of the phase coherence during damping. Using a parametric excitation pump pulse, we observed prolonged phase coherence after the damping, which we call persistent coherence. The time scale was two orders of magnitude longer than the damping time scale of YIG. We will discuss the measurement method and the origin of persistent coherence.