Features
Applications
Introduction
The terahertz (THz) and sub-THz frequency region (100 GHz – 10 THz) of the electromagnetic spectrum bridges the gap between the microwaves and infrared. The “THz gap” is attractive because of many possible applications of terahertz radiation: absorption or reflection spectroscopy, imaging of biological and other objects, THz tomography, ultrafast pump-probe spectroscopy.
Ekspla introduces the main building blocks for any THz system – THz emitter and detector. THz emitter and/or THz detector consists of a microstrip photoconductive antenna fabricated on low-temperature grown GaAs (LT-GaAs) substrate pumped by ultrafast laser with shorter than 150 fs pulse duration. THz radiation is collected and collimated by integrated Si lens, mounted on X-Y stage. Photoconductive antenna geometry, parameters of the Si lens, as well as the properties of LT-GaAs epitaxial layers are optimized for highest THz radiation output efficiency while preserving optimal bandwidth. As a result, typical emitted THz radiation power exceeds 10 µW when pumped by mode-locked Ti:S laser with 100 mW output power and 150 fs pulse duration. FWHM bandwidth of detection system exceeds 700 GHz with usable spectral range of 0.1–3 THz.
THz imaging
THz radiation has an ability to penetrate deep into many organics
materials, which makes THz imaging attractive for imaging of biological samples. Image of the sample can be obtained by raster-scanning of
the sample trough the focused THz beam. Sub-millimeter resolution was reported in scientific literature.
THz Time Domain Spectroscopy
Fig. 1. THz time domain spectrosopy optical layout
The most typical application of THz emitter and detector is THz Time Domain Spectroscopy (THz-TDS). THz-TDS setup is shown in Fig. 1. Subpicosecond pulses of THz radiation are detected
after propagation through a sample and an identical length of a free space. A comparison of the Fourier transforms of these pulse shapes gives the absorption spectra of the sample under investigation.
Pump-Probe THz Experiments
Femtosecond lasers let to investigate ultrafast nonequilibrium dynamics in semiconductors. For this aim, optical-pump-optical-probe techniques are usually employed. In such experiments, an intense optical pump pulse is used to excite free carriers in a sample, while a weaker probe beam monitors changes in its optical properties. In contrary to the optical probe, terahertz probe pulses are non-resonant with the band gap of semiconductor under investigation and, because of this, can be used as direct probes of free-carrier dynamics avoiding numerous experimental artefacts typical for optical-pump-optical-probe systems.
THz Spectroscopy Kit
Our “THz spectroscopy kit” contains all the components necessary to build THz-TDS system. The standard kit consists of photoconductive antenna THz emitter and detector, pump laser beam guiding optics, motorized delay line and bias power supply, THz beam guiding mirrors, sample holder and lock-in amplifier. All the components are assembled and tested on the baseplate of 60×80 cm dimensions. The configuration of the kit can be easily modified, for example, sample holder can be mounted on motorized X-Y stage for imaging experiments.
Fig. 2. THz pulse waveform (a) and spectrum (b)
Typical examples of data collected are shown in Fig. 2. The THz pulse waveform and its Fourier spectrum were measured without sample inserted between emitter and detector in ambient air or argon atmosphere. The distance between emitter and detector is 30 cm.
Requests for custom-made version are welcome!
Ekspla其它光谱仪Ekspla-THz的工作原理介绍
其它光谱仪Ekspla-THz的使用方法?
EksplaEkspla-THz多少钱一台?
其它光谱仪Ekspla-THz可以检测什么?
其它光谱仪Ekspla-THz使用的注意事项?
EksplaEkspla-THz的说明书有吗?
Ekspla其它光谱仪Ekspla-THz的操作规程有吗?
Ekspla其它光谱仪Ekspla-THz报价含票含运吗?
EksplaEkspla-THz有现货吗?
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企业名称
北京欧兰科技发展有限公司
企业信息已认证
企业类型
信用代码
110108003886158
成立日期
2002-06-14
注册资本
50000
经营范围
技术开发、技术转让、技术咨询、技术服务;计算机技术培训;基础软件服务;应用软件服务;计算机系统服务;数据处理;计算机维修;销售计算机、软件及辅助设备、电子产品、机械设备、通讯设备、五金、交电、化工产品(不含危险化学品及一类易制毒化学品)、文化用品、体育用品、日用品。(企业依法自主选择经营项目,开展经营活动;依法须经批准的项目,经相关部门批准后依批准的内容开展经营活动;不得从事本市产业政策禁止和限制类项目的经营活动。)
北京欧兰科技发展有限公司
公司地址
北京市海淀区上地十街1号辉煌国际中心1号楼1006室
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