Electric-field noise in a high-temperature superconducting surface ion trap

High temperature superconducting (HTS) cable termination is an important component of the HTS cable system, which functions to connect the HTS cable and the conventional cable accessory. The stress cones of the HTS cable termination can improve the internal electric field distribution and the electrical insulation strength of the cable termination. In this paper, the mathematical model and equivalent circuit model of the stress cones are built and the genetic algorithm is adopted to the design of 110-kV HTS cable terminal stress cone. The capacitance, radial electric field, axial electric field, voltage, insulation thickness and other parameters of the stress cone were compared before and after the optimization of the stress cone. Finally, the simulations of the stress cone with the optimized structure were made using finite-element analysis software COMSOL to test the optimization result.

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Characteristics of the Shanghai high-temperature superconducting electron-beam ion trap and studies of the space-charge effect under ultralow-energy operating conditions

Physics of Plasmas ◽

10.1063/1.5004426 ◽

2017 ◽

Vol 24 (10) ◽

pp. 103507 ◽

Cited By ~ 3

Author(s):

B. Tu ◽

Q. F. Lu ◽

T. Cheng ◽

M. C. Li ◽

Y. Yang ◽

...

Keyword(s):

Electron Beam ◽

High Temperature ◽

Space Charge ◽

Ion Trap ◽

Space Charge Effect ◽

Operating Conditions ◽

Charge Effect ◽

High Temperature Superconducting ◽

Ultralow Energy ◽

Electron Beam Ion Trap

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Measurements of trapped-ion heating rates with exchangeable surfaces in close proximity

MRS Advances ◽

10.1557/adv.2017.14 ◽

2017 ◽

Vol 2 (41) ◽

pp. 2189-2197 ◽

Cited By ~ 12

Author(s):

D. A. Hite ◽

K. S. McKay ◽

S. Kotler ◽

D. Leibfried ◽

D. J. Wineland ◽

...

Keyword(s):

Electric Field ◽

Quantum Information Processing ◽

Ion Trap ◽

Driving Mechanism ◽

Heating Rates ◽

Ion Heating ◽

Scanned Probe Microscopy ◽

Close Proximity ◽

Field Noise

ABSTRACTElectric-field noise from the surfaces of ion-trap electrodes couples to the ion’s charge causing heating of the ion’s motional modes. This heating limits the fidelity of quantum gates implemented in quantum information processing experiments. The exact mechanism that gives rise to electric-field noise from surfaces is not well-understood and remains an active area of research. In this work, we detail experiments intended to measure ion motional heating rates with exchangeable surfaces positioned in close proximity to the ion, as a sensor to electric-field noise. We have prepared samples with various surface conditions, characterized in situ with scanned probe microscopy and electron spectroscopy, ranging in degrees of cleanliness and structural order. The heating-rate data, however, show no significant differences between the disparate surfaces that were probed. These results suggest that the driving mechanism for electric-field noise from surfaces is due to more than just thermal excitations alone.

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