A New Measurement Method for High Voltages Applied to an Ion Trap Generated by an RF Resonator.

Yunjae Park,Myeongseok Seong,Changhyun Jung,Dongil Dan Cho,Minjae Lee,Taehyun Kim

doi:10.3390/s21041143

Abstract

A new method is proposed to measure unknown amplitudes of radio frequency (RF) voltages applied to ion traps, using a pre-calibrated voltage divider with RF shielding. In contrast to previous approaches that estimate the applied voltage by comparing the measured secular frequencies with a numerical simulation, we propose using a pre-calibrated voltage divider to determine the absolute amplitude of large RF voltages amplified by a helical resonator. The proposed method does not require measurement of secular frequencies and completely removes uncertainty caused by limitations of numerical simulations. To experimentally demonstrate our method, we first obtained a functional relation between measured secular frequencies and large amplitudes of RF voltages using the calibrated voltage divider. A comparison of measured relations and simulation results without any fitting parameters confirmed the validity of the proposed method. Our method can be applied to most ion trap experiments. In particular, it will be an essential tool for surface ion traps which are extremely vulnerable to unknown large RF voltages and for improving the accuracy of numerical simulations for ion trap experiments.

Highlights

Accepted: 4 February 2021An ion trap is an essential physical platform in quantum information processing including quantum computing [1,2,3,4,5] and quantum networks [6], attributed to its high-fidelity quantum gates [7,8] and long coherence time [9]
2.3,applied we can make a voltagewith divider can allow measUnfortunately, a capacitor at radio frequency generally cannot be modeled as a simple ure large voltages applied to the RF electrodes with the dividing ratio of 1:1000
We proposed measuring the absolute amplitude of large RF voltages applied to ion traps using a modularized voltage divider

Summary

Introduction

Accepted: 4 February 2021An ion trap is an essential physical platform in quantum information processing including quantum computing [1,2,3,4,5] and quantum networks [6], attributed to its high-fidelity quantum gates [7,8] and long coherence time [9]. Ions are confined by potentials created using electric fields, which allow fine control of various parameters of the potential [10,11,12,13,14]. To create sufficient potential to trap ions, a Paul trap requires strong oscillating electric fields that are generated by high voltages applied to the radio frequency (RF) electrode of the trap [15]. Resonators such as RLC resonant circuits [16] or helical resonators [17]. Are used as RF voltage amplifiers to generate the high voltages necessary for the ion trap. Only the order of magnitude of voltage gain can be inferred to be proportional to the square root of the quality factor (Q) based on the law of conservation of energy [18,19]: Published: 6 February 2021

Methods

Results

Conclusion