Vibrational properties of CuInP2S6 across the ferroelectric transition

Abstract

In order to explore the properties of a two-sublattice ferroelectric, we measured the infrared and Raman scattering response of CuInP2S6 across the ferroelectric and glassy transitions and compared our findings to a symmetry analysis, calculations of phase stability, and lattice dynamics. In addition to uncovering displacive character and a large hysteresis region surrounding the ferroelectric transition temperature T_C, we identify the vibrational modes that stabilize the polar phase and confirm the presence of two ferroelectric variants with opposite polarizations. Below TC, a poorly understood relaxational or glassy transition at Tg is characterized by local structure changes in the form of subtle peak shifting and activation of low frequency out-of-plane Cu- and In-containing modes. The latter are due to changes in the Cu/In coordination environments and associated order-disorder processes. Moreover, Tg takes place in two steps with another large hysteresis region and significant underlying scattering. Combined with imaging of the room temperature phase separation, this effort lays the groundwork for studying CuInP2S6 under external stimuli and in the ultra-thin limit.

References in corpus (15)

• Layer-dependent Ferromagnetism in a van der Waals Crystal down to the Monolayer Limit
• Phonon and Raman scattering of two-dimensional transition metal dichalcogenides from monolayer, multilayer to bulk material
• LaFeAsO${}_{1-x}$F${}_x$: A low carrier density superconductor near itinerant magnetism
• Suppression of magnetic ordering in XXZ-type antiferromagnetic monolayer NiPS3
• Magnetoelectric MnPS3 thiophosphate as a new candidate for ferrotoroidicity
• Spin-Induced Linear Polarization of Excitonic Emission in Antiferromagnetic van der Waals Crystals
• Linear magneto-electric phase in ultrathin MnPS${}_3$ probed by optical second harmonic generation
• Structural and electronic phase transitions in FePS${}_3$ under the application of pressure
• Isolation and Characterization of Few-layer Manganese Thiophosphite
• Room Temperature Electrocaloric Effect in Layered Ferroelectric CuInP2S6 for Solid State Refrigeration
• Phonon and Thermal Properties of Quasi-Two-Dimensional FePS3 and MnPS3 Antiferromagnetic Semiconductor Materials
• Quasi-Two-Dimensional Magnon Identification in Antiferromagnetic FePS3 via Magneto-Raman Spectroscopy
• Evolution of magnetic order in van-der-Waals antiferromagnet FePS${}_3$ through insulator-metal transition
• Magnetoelastic interaction in the two-dimensional magnetic material MnPS${}_3$ studied by first principles calculations and Raman experiments
• Vibronic interaction in crystals with the Jahn-Teller centers in the elementary energy bands concept

Cited by in corpus (4)

• Cyclic Ferroelectric Switching and Quantized Charge Transport in CuInP${}_2$S${}_6$
• Sliding-mediated ferroelectric phase transition in CuInP2S6 under pressure
• Deciphering the lattice vibrational behaviors of CuInP2S6 by angle-resolved polarized Raman scattering
• Pressure-Driven Structural Phase Competition and Functional Response in Layered LiInP2S6