The electrocaloric (EC) effect offers a promising energy-efficient and clean cooling technology. We present the first direct measurements of EC temperature change in a new family of EC fluids, ferroelectric nematic liquid crystals (FNLCs), demonstrating in two such materials temperature jumps of ∣ΔTj∣ ~ 0.2 K for field changes as low as ΔE ~ 0.1 Vμm−1. Indirect measurements of adiabatic temperature change ∣ΔT∣ confirm that these direct measurements are an underestimate and that ΔE = 2 Vμm−1 can induce up to ∣ΔT∣ ~ 1.6 K, yielding EC strengths ∣ΔT/ΔE∣ up to 100% higher than incumbent materials. For temperature spans of 5-10 K, we predict a coefficient of performance of ~21-40. We find ∣ΔT∣ ~ 1 K for >100 FNLCs that collectively span all temperatures between 0∘C and 100∘C. This, together with the new device concepts conceivable with fluid EC materials, offers huge potential for cooling applications.
@article{arxiv.2510.26386,
title = {Large electrocaloric strength in ferroelectric nematic liquid crystals with a tuneable operational temperature range},
author = {Diana I. Nikolova and Rachel Tuffin and Mengfan Guo and Neil D. Mathur and Xavier Moya and Peter Tipping and Richard J. Mandle and Helen F. Gleeson},
journal= {arXiv preprint arXiv:2510.26386},
year = {2025}
}