Time-resolved photoemission apparatus achieving sub-20-meV energy resolution and high stability
Time-resolved photoemission apparatus achieving sub-20-meV energy resolution and high stability
复制标题
DOI：
10.1063/1.4903788
复制
发表时间：
2014-12-01
影响因子：
1.6
通讯作者：
Shin, S.
中科院分区：
文献类型：
--
作者：
Ishida, Y.;Togashi, T.;Shin, S.
本文介绍了一种由半球形分析器和脉冲激光源组成的时间和角度分辨光电发射装置。我们证明了1.48-eV的泵和5.92-eV的探针测量在>= 10.5-meV和>= 240-fs的分辨率，通过使用相当单色的170-fs的脉冲从再生放大的钛：蓝宝石激光器系统，通常工作在250 kHz。该装置能够分辨铜酸盐超导体Bi_2Sr_2CaCu_2 O_（8 + δ）的未占据态中的光学填充超导峰。给出了在Bi（111）面上记录的数据集。技术描述包括以下内容：一个简单的程序，以微调的泵浦和探测光束的时空重叠和它们的直径;实现长期稳定的系统，使一个归一化的数据集采集;改变重复率，利用声光调制器和分频电路。(C)2014 AIP Publishing LLC.
The paper describes a time-and angle-resolved photoemission apparatus consisting of a hemispherical analyzer and a pulsed laser source. We demonstrate 1.48-eV pump and 5.92-eV probe measurements at the >= 10.5-meV and >= 240-fs resolutions by use of fairly monochromatic 170-fs pulses delivered from a regeneratively amplified Ti: sapphire laser system operating typically at 250 kHz. The apparatus is capable to resolve the optically filled superconducting peak in the unoccupied states of a cuprate superconductor, Bi2Sr2CaCu2O8+delta. A dataset recorded on Bi(111) surface is also presented. Technical descriptions include the followings: A simple procedure to fine-tune the spatio-temporal overlap of the pump-and-probe beams and their diameters; achieving a long-term stability of the system that enables a normalization-free dataset acquisition; changing the repetition rate by utilizing acoustic optical modulator and frequency-division circuit. (C) 2014 AIP Publishing LLC.