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Published on: May 25, 2021
Novel scaling laws for the Langmuir-Blodgett solutions in cylindrical and spherical diodes
1Engineering Product Development, Singapore University of Technology and Design, Singapore 138682, Singapore.
Abstract:
It is found that the Langmuir-Blodgett solutions for the space charge limited current density, for both cylindrical and spherical diodes, may be approximated by Japp=(4/9)ε0sqrt[(2e/m)](Ec3/2/sqrt[D]) over a wide range of parameters, where Ec is the surface electric field on the cathode of the vacuum diode and D is the anode-cathode spacing. This dependence is valid whether Ra/Rc is greater than or less than unity, where Ra and Rc are, respectively, the anode and cathode radius. Minor empirical corrections to the above scaling yield fitting formulas that are accurate to within 5% for 3×10(-5)
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