Tuning Interfacial Thermal Transport through Phase Engineering in 2D Ferroelectrics

As a 2D material with distinctive ferroelectric properties, In₂Se₃ offers significant potential for the applications in information memory and advanced data storage technologies. It also exhibits a complex phase diagram that is highly sensitive to temperature and pressure variations, resulting in diverse lattice configurations. While extensive studies have focused on the phase transition behavior of In₂Se₃, its impact on phonon transport remains largely unexplored. In this work, the interfacial thermal transport in mechanically exfoliated few-layer α-In₂Se₃ is probed for the first time. Using Raman spectroscopy and electrical property measurements, a significant shift is observed in both the Raman peaks and electrical characteristics ≈ 65 K, where the electrical resistance changes by two orders of magnitude. Furthermore, by using the 3ω method, notable variations are detected in the interfacial thermal resistance near 65 K, indicating a phase transition induced by lattice distortion at low temperatures. In contrast, no comparable changes appeared ≈ 500 K, suggesting that high-temperature phase transitions induce subtler impacts on thermal transport. The ability to modulate the interfacial thermal resistance through phase transitions in 2D ferroelectrics In₂Se₃ presents a promising approach to addressing the thermal management challenges of next-generation data storage technologies.