A phenomenon called near-field surface photovoltage is presented. It is based on inducing photovoltage only at a semiconductor space-charge region using near-field illumination. The photovoltage is obtained by measuring the contact potential difference between an optical near-field force sensor and a semiconductor surface under illumination. It is shown that the near-field illumination induces photovoltage at the surface which is principally different from photovoltage induced by far-field illumination. The mechanisms that govern the different far-field and near-field photovoltage response are discussed.
ASJC Scopus subject areas
- Physics and Astronomy (miscellaneous)