Jahn-Teller Effect in Diamond-like Carbon Film

TL;DR

This study analyzes the Jahn-Teller effect in diamond-like carbon films using semi-theoretical methods to interpret UV-visible spectra, revealing stress-related spectral shifts and state splittings.

Contribution

It introduces a semi-theoretical approach linking Jahn-Teller distortions to stress in films, aligning spectral analysis with experimental data.

Findings

Identification of six Jahn-Teller related absorption lines

Correlation of spectral shifts with stress levels

Observation of doubled splitting in excited states

Abstract

The Jahn-Teller effect used semi-theoretically to analyse UV-visible spectra of the diamond like-carbon films on Si substrates. By deconvolution of UV-visible absorption spectra of the typical films, different absorption lines found. For each sample, six lines which were related to $\V^\circ$ by Jahn-Teller effect are distinguished. Our theoretical approach based on distortion of the $\V^\circ$ as the consequence of the stress in the films, is in agreement with experimental results. The shift of the Jahn-Teller lines toward the zero phonon line of $\V^\circ$ were found in accordance to stress decrease in the films. The difference between room temperature and low temperature spectra is discussed. We found that the splitting of the excited state of $\V^\circ$ in the films under stress is twice as large as that of the ground state.