Ferroelectric domain switching in c-axis-oriented epitaxial Pb(Zr 0.2 Ti 0.8 )O 3 thin films was studied using biased scanning probe microscopy tips. While linear and logarithmic dependence of domain size on tip bias and writing time, respectively, are well known, we report an additional linear dependence on relative humidity in the 28-65% range. We map out the switched domain size as a function of both the tip bias and the applied pulse time and describe a growth-limited regime for very short pulses and a nucleation-limited regime for very low tip bias. Using 'interrupted-switching' measurements, we probe the nucleation regime with subcritical pulses and identify a surprisingly long relaxation time on the order of 100 ms, which we relate to ionic redistribution both on the surface and within the thin film itself.

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Crystallographic direction dependence of direct current field induced strain and phase transitions in Na0.5Bi0.5TiO3-x%BaTiO3 single crystals near the morphotropic phase boundary Appl. Phys. Lett. 101, 141912 (2012) Enhanced piezoelectric and antiferroelectric properties of high-TC perovskite of Zr-substituted Bi(Mg1/2Ti1/2)O3-PbTiO3 J. Appl. Phys. 112, 074101 (2012) Pinned interface dipole-induced tunneling electroresistance in ferroelectric tunnel junctions: A theoretical investigation J. Appl. Phys. 112, 054104 (2012) The origin of magnetism in perovskite ferroelectric ABO3 nanoparticles (A=K,Li; B=Ta,Nb or A=Ba,Sr,Pb; B=Ti)

To optimize the performance of multifunctional carbon nanotube-ferroelectric devices, it is necessary to understand both the polarization and charge dynamics effects on their transconductance. Directly comparing ferroelectric Pb(Zr 0.2 Ti 0.8 )O 3 and dielectric SrTiO 3 field effect transistors, we show that the two effects strongly compete, with transient charge dynamics initially masking up to 40% of the ferroelectric field effect. For applications, it is therefore crucial to maximize the quality of the ferroelectric film and the interface with the carbon nanotube to take full advantage of the switchable polarization.

Understanding and controlling the motion, stability, and equilibrium configuration of ferroelectric domain walls is key for their integration into potential nanoelectronic applications, such as ferroelectric racetrack memories. Using piezoresponse force microscopy, we analyze the growth and roughness of ferroelectric domains in epitaxial thin film Pb(Zr0.2Ti0.8)O3, driven by the electric fields at straight edges of planar electrodes at two different temperatures. This device relevant geometry allows us to confirm that the domain walls are well described as one-dimensional monoaffine elastic interfaces driven in random-bond disorder. However, we observe a progressive increase in roughness as initially flat domain walls move through the disorder landscape, which could prove a significant limiting factor for racetrack-type memories using ferroelectrics.