Critical splay fluctuations and colossal flexoelectric effect above the nonpolar to polar nematic phase transition
نویسندگان
چکیده
The recent discovery of nematic liquid crystals with polar order (ferroelectric) has created immense interest. Despite intensive research, several physical properties this crystal are yet to be investigated and understood. Here, we report experimental studies on the surface alignment, birefringence, flexoelectric coefficient a $({N}_{\mathrm{F}})$ crystal. Our experiments directly reveal that splay fluctuations influence birefringence degrees above nonpolar $(N)$ phase transition temperature, heat capacity exponent obtained from tilt angle is close value reported in adiabatic scanning calorimetry measurements. shows power-law dependence temperature. It demonstrates strong coupling pretransitional ferroelectric field. These results important for applications as well understanding all effects crystals.
منابع مشابه
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ژورنال
عنوان ژورنال: Physical Review Materials
سال: 2023
ISSN: ['2476-0455', '2475-9953']
DOI: https://doi.org/10.1103/physrevmaterials.7.035603