Fiber-mounted electro-optic probe for microwave electric-field measurement in plasma environment

Abstract

The demand for greater precision in electric-field measurements is increasing. To meet this demand, NTT Microsystem Integration Laboratories has developed an electro-optic (EO) probe that is mounted on the tip of an optical fiber and has no metal components. This article describes the basic principles and improvements in sensitivity stability and thermal and magnetic resistance of the EO probe. It also presents the results of microwave electric-field measurements conducted in an electron cyclotron resonance ion engine installed on an asteroid explorer under the collaboration of NTT and the Japan Aerospace Exploration Agency.