Transparent Electrodes for High E-Field Production Using A Buried ITO Layer

TL;DR

This paper introduces a novel transparent electrode design with a buried ITO layer that withstands high electric fields without arcing, enabling precise electric field control in atomic physics experiments.

Contribution

The authors present a new electrode configuration with a buried ITO layer that prevents electrical breakdown at high fields, suitable for optical access in atomic physics setups.

Findings

Electrodes operate without arcing up to 120 kV/cm.

Electric fields up to 18 kV/cm verified inside a vacuum cell.

Observed atom loss linked to field emission effects.

Abstract

We present a design and characterization of optically transparent electrodes suitable for atomic and molecular physics experiments where high optical access is required. The electrodes can be operated in air at standard atmospheric pressure and do not suffer electrical breakdown even for electric fields far exceeding the dielectric breakdown of air. This is achieved by putting an ITO coated dielectric substrate inside a stack of dielectric substrates, which prevents ion avalanche resulting from Townsend discharge. With this design, we observe no arcing for fields of up to 120 kV/cm. Using these plates, we directly verify the production of electric fields up to 18~kV/cm inside a quartz vacuum cell by a spectroscopic measurement of the dc Stark shift of the $5^2S_{1/2} \rightarrow 5^2P_{3/2}$ transition for a cloud of laser cooled Rubidium atoms. We also report on the shielding of the electric field and residual electric fields that persist within the vacuum cell once the electrodes are discharged. In addition, we discuss observed atom loss that results from the motion of free charges within the vacuum. The observed asymmetry of these phenomena on the bias of the electrodes suggests that field emission of electrons within the vacuum is primarily responsible for these effects and may indicate a way of mitigating them.