In-situ electrical and thermal transport properties of FeySe1-xTex films with ionic liquid gating

We combine in-situ electrical transport and Seebeck coefficient measurements with the ionic liquid gating technique to investigate superconductivity and the normal state of FeySe1-xTex (FST) films. We find that the pristine FST films feature a non-Fermi liquid temperature dependence of the Seebeck coefficient, i.e., S/T ~ AS lnT, and AS is strongly correlated with the superconducting transition temperature (Tc). Ionic liquid gating significantly raises Tc of FST films, for which the Seebeck coefficient displays a novel scaling behavior and retains the logarithmic temperature dependence. Moreover, a quantitative relationship between the slope of T-linear resistivity (A\r{ho}) and Tc for gated films is observed, i.e., (A\r{ho})1/2 ~ Tc, consistent with previous reports on cuprates and FeSe. The scaling behaviors of AS and A\r{ho} point to a spin-fluctuation-associated transport mechanism in gated FeySe1-xTex superconductors.Comment: 12 pages,5 figure

Anomalous in-plane magnetoresistance of electron-doped cuprate La2−xCexCuO4±δ

We report systematic in-plane magnetoresistance measurements on the electron-doped cuprate La2−xCexCuO4±δ thin films as a function of Ce doping and oxygen content in the magnetic field up to 14T. A crossover from negative to positive magnetoresistance occurs between the doping level x = 0.07 and 0.08. Above x = 0.08, the positive magnetoresistance effect appears, and is almost indiscernible at x = 0.15. By tuning the oxygen content, the as-grown samples show negative magnetoresistance effect, whereas the optimally annealed ones display positive magnetoresistance effect at the doping level x = 0.15. Intriguingly, a linear-field dependence of in-plane magnetoresistance is observed at the underdoping level x = 0.06, the optimal doping level x = 0.1 and slightly overdoping level x = 0.11. These anomalies of in-plane magnetoresistance may be related to the intrinsic inhomogeneity in the cuprates, which is discussed in the framework of network model

Boosting attachment security to cope with threats: Behavioral and ERPs findings

Attachment security describes a sense of safety and security felt by individuals and promotes mental health. The mechanism by which attachment security buffers against psychological threat remains unclear, however. Here, we explored how attachment security attenuates the response to threatening information using a signal detection theory (SDT) and event-related potentials (ERPs) approach. Participants were assigned to an attachment security priming condition or a control condition. After a priming procedure, behavioral data and electroencephalography (EEG) signals were recorded while participants categorized threatening and neutral pictures. Our behavioral results revealed that attachment security biased participant responses to categorizing the two types of pictures; participants in the control condition exhibited a tendency to categorize stimuli as threatening, whereas those in the attachment security condition tended to categorize stimuli as neutral. Meanwhile, attachment security priming modulated early attention processes, reflected by an increased P200. The findings reported here suggest that attachment security buffers against external threats by modulating individual response preferences, the effects of which manifest in the early stages of attentional processing

Attachment Security Priming Delayed Negative Information-Related Attentional Disengagement Among Anxiously Attached Individuals: Evidence From Behavioral and Functional MRI Experiments

Although attachment security has been found to attenuate people's experience of unpleasant information, how it modulates the attentional process toward such information remains unknown. The present study examined this issue by employing the dot-probe task in functional MRI. After completing the Experiences in Close Relationships-Revised questionnaire (ECR-R), 39 participants were asked to complete the dot-probe task in two conditions: the attachment security priming condition and neutral priming condition. The behavioral results revealed that individuals with high level of attachment anxiety exhibited larger attention disengagement from negative traits in the security priming condition than in the control condition. Correspondingly, the brain regions involved in attention regulation and shifting, such as the posterior cingulate and bilateral parietal area, were less activated among high anxiously attached individuals in the security priming condition. These results suggest a role of attachment security priming in regulating the emotional response in anxiously attached individuals during the attentional stage