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Thin-film lead–zirconate–titanate (PZT) capacitors with composition gradients normal to the substrate were fabricated via a novel technique using pulsed laser deposition. These capacitors exhibited large polarization offsets when driven by an alternating electric field. The direction of the offsets depended on the direction of the gradient with respect to the substrate. The largest offset, greater than 400 μC/cm2 when driven with a 50 V/μm field, was nearly an order of magnitude greater than any reported for other graded ferroelectric films. This difference is attributed to both the high spontaneous polarization of PZT and the high-quality films obtained by pulsed laser deposition.

Previous research provides evidence for a dissociable embodied route to spatial perspective-taking that is under strategic control. The present experiment investigated further the influence of strategy on spatial perspective-taking by assessing whether participants may also elect to employ a separable “disembodied” route loading on inhibitory control mechanisms. Participants (N = 92) undertook both the “own body transformation” (OBT) perspective-taking task, requiring speeded spatial judgments made from the perspective of an observed figure, and a control task measuring ability to inhibit spatially compatible responses in the absence of a figure. Perspective-taking performance was found to be related to performance on the response inhibition control task, in that participants who tended to take longer to adopt a new perspective also tended to show a greater elevation in response times when inhibiting spatially compatible responses. This relationship was restricted to those participants reporting that they adopted the perspective of another by reversing left and right whenever confronted with a front-view figure; it was absent in those participants who reported perspective-taking by mentally transforming their spatial orientation to align with that of the figure. Combined with previously published results, these findings complete a double dissociation between embodied and disembodied routes to spatial perspective-taking, implying that spatial perspective-taking is subject to modulation by strategy, and suggesting that embodied routes to perspective-taking may place minimal demands on domain general executive functions.

Ferroelectric films with composition gradients normal to the substrate have recently been reported to exhibit anomalously large polarization offsets when hysteresis loops are driven with an ac voltage and measured using a Sawyer–Tower (ST) circuit. These offsets have been reported in graded Pb(Zr, Ti)O3 (over 400 μC/cm2) and graded (Ba, Sr)TiO3 (30 μC/cm2) films. In this work, it was found that the offset observed in graded Pb(Zr, Ti)O3 films can be attributed to development of a dc voltage across the ac-voltage driven film, rather than a polarization offset. Recognition of this result reduces these previously reported offset values by a factor of Cs/Cref, where Cref and Cs are the reference and sample capacitances, respectively, used in the ST circuit. These dc-voltage offsets still represent a phenomenon which may lead to novel device applications.