Electron‒Photon Interactions under the Size Limitation of the Conductivity in Single Semiconductor Quantum-Sized Particles in an Interelectrode Nanogap

Abstract

In quantum-sized InSb, PbS, HgSe, and CdSe semiconductor particles under the tunneling conduction, the photoconductivity with a multiplicity factor of up to two orders of magnitude is observed for the interband transitions of carriers, which is caused by the removal of the single-electron current and Coulomb confinement blocking. Under the electron-size quantum confinement, the interband and interlevel photoconductivity does not manifest itself. In this case, the resonant current (quantum conductivity) peaks in the I–V characteristics under exposure to light of any wavelength in the range of 0.4–1.2 μm vanish or shift towards lower voltages. This is explained within the model of electron heating by the electric field of a light wave. The energy minimum of the quanta detected in this case is estimated as 100 meV. The results obtained can be used to in uncooled IR detectors, including photon ones.