摘要
通过测量音叉振动速度幅值和相位频率特性,得到共振吸收和色散频域特征,分析阻尼强度对共振吸收频谱宽度的影响.由时域测量得到不同阻尼情形的共振弛豫时间,研究共振吸收频谱宽度与弛豫时间的物理关联.采用离散傅里叶变换方法,从理论上探讨由共振弛豫时域测量数据获取共振吸收的频域参量.研究结果表明,若共振弛豫时间较长,意味着激发态能级宽度比较窄;反之,则是激发态能级宽度比较宽.
With measuring the amplitude-and phase-frequency characteristics of vibration speed for tuning fork,its resonance absorption and dispersion in frequency-domain were obtained.The influence of damping on frequency spectrum width of resonance absorption was analyzed,and then the resonance relaxation time for different cases was measured in time-domain.The correlation between the frequency spectrum width and the relaxation time of resonance absorption was studied.Furthermore,the parameters of resonance absorption in frequency-domain were obtained from the data of resonance relaxation in time-domain using DFT.The results showed that the energy level width of excited state was narrower for longer resonance relaxation time;otherwise,the result was reversed.
作者
李潮锐
LI Chao-rui(School of Physics,Sun Yat-sen University,Guangzhou 510275,China;National Demonstration Center for Experimental Physics Education,Sun Yat-sen University,Guangzhou 510275,China)
出处
《物理实验》
2020年第2期12-15,共4页
Physics Experimentation
基金
中山大学物理学人才培养支撑条件建设项目（No.J1210034）
中山大学本科教学质量工程项目（No.2018WL-ZLJG026,No.2019WL-ZLJG004）
关键词
音叉
受迫振动
共振吸收
弛豫时间
频率特性
tuning fork
forced vibration
resonance absorption
relaxation time
frequency characteristic
作者简介
李潮锐(1962-),男,广东汕头人,中山大学物理学院副教授,博士,主要从事凝聚态电磁性质研究.
