Observation of new quantum interference effect in solids

TL;DR

This paper reports a novel quantum interference effect in solids where geometric modifications induce destructive interference of de Broglie waves, leading to increased Fermi energy and decreased work function, supported by theoretical and experimental evidence.

Contribution

It introduces a new quantum interference phenomenon in solids caused by geometric patterning, affecting electron states and work function, with experimental validation in gold and silica films.

Findings

Fermi energy level increases with patterned surface modifications.

Work function decreases by up to 0.5 eV in gold films.

Quantum interference effects are experimentally observed and characterized.

Abstract

In order to achieve quantum interference of free electrons inside a solid, we have modified the geometry of the solid so that de Broglie waves interfere destructively inside the solid. Quantum interference of de Broglie waves leads to a reduction in the density of possible quantum states of electrons inside the solid and increases the Fermi energy level. This effect was studied theoretically within the limit of the quantum theory of free electrons inside the metal. It has been shown that if a metal surface is modified with patterned indents, the Fermi energy level will increase and consequently the electron work function will decrease. This effect was studied experimentally in both Au and SiO2 thin films of special geometry and structure. Work function reductions of 0.5 eV in Au films and 0.2 eV in SiO2 films were observed. Comparative measurements of work function were made using the Kelvin Probe method based on compensation of internal contact potential difference. Electron emission from the same thin films was studied by two independent research groups using Photoelectron Emission Microscopy (PEEM).