Related Experiment Video
Updated: Mar 11, 2026

Implementation of a Reference Interferometer for Nanodetection
Published on: April 26, 2014
Upgraded millimeter-wave interferometer for measuring the electron density during the beam extraction in the negative
T Tokuzawa1, M Kisaki1, K Nagaoka1
1National Institute for Fusion Science, 322-6 Oroshi-cho, Toki 509-5292, Japan.
Abstract:
The upgraded millimeter-wave interferometer with the frequency of 70 GHz is installed on a large-scaled negative ion source. Measurable line-averaged electron density is from 2 × 1015 to 3 × 1018 m-3 in front of the plasma grid. Several improvements such as the change to shorter wavelength probing with low noise, the installation of special ordered horn antenna, the signal modulation for a high accuracy digital phase detection, the insertion of insulator, and so on, are carried out for the measurement during the beam extraction by applying high voltage. The line-averaged electron density is successfully measured and it is found that it increases linearly with the arc power and drops suddenly at the beam extraction.
Related Concept Videos
Mass Analyzers: Common Types
Mass Analyzers: Overview
Inductively Coupled Plasma–Mass Spectrometry (ICP–MS): Overview
Inductively Coupled Plasma Atomic Emission Spectroscopy: Instrumentation
There are three main types of inductively coupled plasma atomic emission spectroscopy (ICP-AES) instruments: sequential, simultaneous multichannel, and Fourier transform instruments, with the latter being less commonly used....

