Ion heating induced by near-field thermal noise of superconducting ion chip

Abstract

Abstract:

Ion heating effect incuced by near-field thermal noise of superconducting ion chip at different temperatures is investigated based on fluctuation-dissipation theorem. The approximate expressions of electric field fluctuation spectral density under different conditions are obtained by the electric field Green function and multi-layer reflection coefficients. For pure Nb electrode, the near-field thermal noise spectral density is inversely proportional to the electrode thickness when the temperature T is 295 K. The near-field thermal noise spectral density is irrelevant with the electrode thickness when T is 4 K, and the near-field thermal noise can be reduced by over ten orders of magnitude comparing to the case of room temperature. The case that there are thin films on the surface of niobium electrode is analyzed. Results show that the electric field fluctuation induced by film occupies the main position. The noise spectral density is proportional to the thickness. When chip temperature decreases to 4 K, the thermal noise decreases by 5 to 6 orders of magnitude.

Key words: quantum optics; near-field thermal noise; fluctuation-dissipation theorem; superconducting ion chip

CLC Number:

O431.2

XU Zhibing, ZHANG Bo, YANG Bo, LIU Zilong, MAO Rusheng. Ion heating induced by near-field thermal noise of superconducting ion chip[J]. J4, 2018, 35(4): 432-438.

References

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