Fig. 1: P-E loops under pressure.
From: Anomalous polarization enhancement in a van der Waals ferroelectric material under pressure
a Crystal structure of CIPS viewed along the layer normal direction (c∗ axis) and b axis, respectively, with an octahedral sulfur cage showing various copper sites at room temperature. The size of the Cu atom represents its occupation probability. b Schematic of the high-pressure experimental setup. A CIPS ferroelectric crystal is held in a piston pressure cell. The yellow line embedded in epoxy represents an enameled copper wire. c Polarization-electric field (P-E) hysteresis loops of CIPS measured at different frequencies under ambient conditions. d, e P-E loops of CIPS measured at 1 kHz under representative pressures. f Remanent polarization (Pr) as a function of pressure, obtained from d and e. The error bars were estimated from the electrode areas.
