Nanoindentation of the a and c domains in a tetragonal BaTiO3 single crystal

Nanoindentation in conjunction with piezoresponse force microscopy was used to study domain switching and to measure the mechanical properties of individual ferroelectric domains in a tetragonal BaTiO3 single crystal. It was found that nanoindentation has induced local domain switching; the a and c domains of BaTiO3 have different elastic moduli but similar hardness. Nanoindentation modulus mapping on the a and c domains further confirmed such difference in elasticity. Finite element modeling was used to simulate the von Mises stress and plastic strain profiles of the indentations on both a and c domains, which introduces a much higher stress level than the critical value for domain nucleation

Non-Abelian Proca model based on the improved BFT formalism

We present the newly improved Batalin-Fradkin-Tyutin (BFT) Hamiltonian formalism and the generalization to the Lagrangian formulation, which provide the much more simple and transparent insight to the usual BFT method, with application to the non-Abelian Proca model which has been an difficult problem in the usual BFT method. The infinite terms of the effectively first class constraints can be made to be the regular power series forms by ingenious choice of $X_{\alpha \beta}$ and $\omega^{\alpha \beta}$-matrices. In this new method, the first class Hamiltonian, which also needs infinite correction terms is obtained simply by replacing the original variables in the original Hamiltonian with the BFT physical variables. Remarkably all the infinite correction terms can be expressed in the compact exponential form. We also show that in our model the Poisson brackets of the BFT physical variables in the extended phase space are the same structure as the Dirac brackets of the original phase space variables. With the help of both our newly developed Lagrangian formulation and Hamilton's equations of motion, we obtain the desired classical Lagrangian corresponding to the first class Hamiltonian which can be reduced to the generalized St\"uckelberg Lagrangian which is non-trivial conjecture in our infinitely many terms involved in Hamiltonian and Lagrangian.Comment: Notable improvements in Sec. I

How donor's regulatory focus changes the effectiveness of a sadness-evoking charity appeal

Past research offers conflicting findings on whether sadness-evoking charity appeals help solicit a donation. To reconcile these findings, we introduce prospective donors' regulatory focus as a moderator for understanding when and why sadness appeals motivate or demotivate giving. Specifically, we propose that the sense of helplessness or loss of control associated with sadness appeals increases donors' sensitivity to advertiser's manipulative persuasion tactics, as those tactics can threaten donors' control over their donation decision. As a result, sadness appeals are more likely to activate persuasion knowledge among prevention- (vs. promotion-) oriented donors who tend to be vigilant against manipulative persuasion attempts. Across six main studies and two supplementary studies, we find that a prevention (vs. promotion) focus discourages charitable giving when it is solicited using a sadness appeal, whereas regulatory focus does not affect the giving when other emotion appeals (e.g., happiness appeal or guilt appeal) are used. We find that a prevention (vs. promotion) focus demotivates donation solicited by a sadness appeal because it activates persuasion knowledge that evaluates solicitor's motive behind the sadness appeal, resulting in increased skepticism, dampened feelings of sympathy, and consequently, reduced charitable giving. However, when persuasion knowledge is deactivated (e.g., when donors' cognitive capacity is constrained or the soliciting charity has a reliable reputation), regulatory focus no longer affects donor skepticism, sympathy, and charitable giving, even when a sadness appeal is used to call for donation

Directional interacting whispering gallery modes in coupled dielectric microdisks

We study the optical interaction in a coupled dielectric microdisks by investigating the splitting of resonance positions of interacting whispering gallery modes (WGMs) and their pattern change, depending on the distance between the microdisks. It is shown that the interaction between the WGMs with odd parity about y-axis becomes appreciable at a distance less than a wavelength and causes directional emissions of the resulting interacting WGMs. The directionality of the interacting WGMs can be understood in terms of an effective boundary deformation in ray dynamical analysis. We also discuss about the oscillation of the splitting when the distance is greater than a wavelength.Comment: 7 pages, 10 figure