charge transport measurement method Kelvin probe method Kelvin method A measurement method for determining the contact potential difference or difference in work functions between the sample and a reference electrode. In this method, the probe, which is made of a material with a known work function (commonly tungsten or platinum), is arranged close to the sample surface as a parallel-plate capacitor with a small spacing. The probe is vibrated, causing a change in the capacitance between the electrodes, resulting in a small ac current. The work function difference is measured by applying an opposing external bias voltage such that the ac current is zero. vibrating capacitor method 2009-09-23T06:07:50Z CHMO:0002458 https://orcid.org/0000-0001-5985-7429