Spin-Peierls transition in carbynoid conductors: infrared absorption study

TL;DR

This study uses infrared absorption to investigate the spin-Peierls transition in carbynoid conductors, revealing novel spin and charge phenomena, including the first identification of electric spin moments and antiferroelectric spin wave resonance.

Contribution

It provides new insights into the spin-Peierls transition in carbynoids, identifying electric spin moments, AFESWR, and the role of impurities as dopants, expanding understanding of 1D conductors.

Findings

Identification of antiferroelectric spin wave resonance (AFESWR) in carbynoids.

First observation of electric spin moment with pure imaginary value.

Proposal that topological solitons (SPS) have both electric and magnetic spin moments.

Abstract

The results of IR-studies in quasi-1D carbynoid films produced by dehydrohalogenation of poly(vinilidene fluoride) are in good agreement with the assumption that carbynoid films studied are generalized spin -Peierls conductors, the metal to insulator transition in which can be described in the frame of t-J model. Residual atoms of fluorine, hydrogen and atoms of main technological impurity oxygen in the form of various complexes in interchain space are suggested to be spin - (or joint spin - and electrical) conductivity dopants. Antiferroelectric spin wave resonance (AFESWR) being to be optical analogue of antiferromagnetic spin wave resonance has been identified for the first time. Electric spin-Peierls polaron lattice in C-C -bonds is proposed to be responsible for the observed AFESWR both in starting PWDF films and in carbynoid B-films (the samples with the least impurity content). Electric spin moment with pure imaginary value predicted by Dirac as early as 1928 was identified for the first time. Electric spin-Peierls polarons are proposed to be electric spin moment carriers. It has been established that topological solitons, earlier called spin-Peierls solitons (SPS), are simultaneously active, unlike to topological solitons with nonzero spin in \textit{trans}-polyacetylene, in both optical and magnetic resonance spectra.It is explained in suggestion that SPS possess by both electric and magnetic spin moments which can be considered as two components of complex electromagnetic spin vector as a single whole. SPS proposed to be consisting of two coupled domain walls in both magnetic and electric generalized spin density wave (GSDW), produced by electromagnetic spin-Peierls transition in its generalized form in $\pi$ - and $\sigma$ -subsystems of carbynoids.