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Abstract The understanding of domain dynamics in ferroelectric materials is crucial for optimizing their performance in piezoelectric and electro‐optic applications. Although previous studies have focused on static domain structures and macroscopic characteristics, the time‐resolved approach of domains remains largely unexplored. In this study, we compare the dynamic responses of direct current (DC) and alternating current (AC) poled [001]‐oriented rhombohedral Pb(Mg1/3Nb2/3)O3–PbTiO3(PMN–PT) single crystals using X‐ray photon correlation spectroscopy (XPCS) during the application of external electric fields. Our results demonstrate that the AC‐poled sample exhibit enhanced reconfiguration of domain variants in response to driving fields compared to the DC‐poled counterpart, as evidenced by accelerated correlation decay and faster relaxation time. This phenomenon is attributed to enhanced reversible domain wall motion achieved through AC poling, which facilitates field‐induced domain realignment. These findings provide insight into the relationship between dynamics and macroscopic properties in relaxor‐PT single crystals for high‐performance applications.
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Ferroelectric Domain Wall Engineering Enables Thermal Modulation in PMN–PT Single Crystals
Abstract Acting like thermal resistances, ferroelectric domain walls can be manipulated to realize dynamic modulation of thermal conductivity (k), which is essential for developing novel phononic circuits. Despite the interest, little attention has been paid to achieving room‐temperature thermal modulation in bulk materials due to challenges in obtaining a high thermal conductivity switching ratio (khigh/klow), particularly in commercially viable materials. Here, room‐temperature thermal modulation in 2.5 mm‐thick Pb(Mg1/3Nb2/3)O3–xPbTiO3(PMN–xPT) single crystals is demonstrated. With the use of advanced poling conditions, assisted by the systematic study on composition and orientation dependence of PMN–xPT, a range of thermal conductivity switching ratios with a maximum of ≈1.27 is observed. Simultaneous measurements of piezoelectric coefficient (d33) to characterize the poling state, domain wall density using polarized light microscopy (PLM), and birefringence change using quantitative PLM reveal that compared to the unpoled state, the domain wall density at intermediate poling states (0<d33<d33,max) is lower due to the enlargement in domain size. At optimized poling conditions (d33,max), the domain sizes show increased inhomogeneity that leads to enhancement in the domain wall density. This work highlights the potential of commercially available PMN–xPT single crystals among other relaxor‐ferroelectrics for achieving temperature control in solid‐state devices.
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- Award ID(s):
- 2011978
- PAR ID:
- 10409651
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Advanced Materials
- Volume:
- 35
- Issue:
- 22
- ISSN:
- 0935-9648
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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