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We propose and demonstrate a widely tunable optical filter, realized by angle tuning a volume holographic grating. The volume holographic grating selectively drops a narrow portion of the signal bandwidth into a fiber while passing through the rest of the ...
The phenomenon of polarization imprint consisting of the development of a preferential polarization state in ferroelectric films is known as one of the major issues impacting the development of high density ferroelectric memories. According to the commonly ...
We report a novel three-contact vertical-cavity surface-emitting laser (VCSEL) for use in polarization-sensitive optical applications. The device consists of two vertical cavities, coupled by a common mirror. We demonstrate that one can independently choos ...
The orientation dependence of the longitudinal piezoelectric coefficient, d(33)(*), is investigated as a function of temperature in BaTiO3 and PbTiO3 crystals using the Landau-Ginsburg-Devonshire theory. We show that a presence of the ferroelectric-ferroel ...
The domain nucleation and growth during polarization switching in Pb(Zr,Ti)O-3 (PZT) ferroelectric thin film capacitors with Pt top (TE) and bottom electrodes (BE) were studied by means of atomic force microscopy (AFM). The experimental configuration used ...
This article reviews recent advances in the studies of the piezoelectric properties of perovskite materials. Perovskite compositions are the best known and the largest family of ferroelectric and piezoelectric materials.: The dependence of the longitudinal ...
We report on results of the fabrication and the micro-reflectance measurement of GaN photonic crystals. The etching performance of GaN has been studied with a conventional reactive ion etching system and SiCl4 plasma. We obtained an etch rate of 100 nm/min ...
The longitudinal d(33) piezoelectric coefficient was studied in rhombohedral Pb(Zr0.6Ti0.4)O-3 thin films with (111), (100), and "random" orientation. The largest d(33) was found in (100)-oriented films and the smallest along the polarization direction in ...
We studied polarization switching of 295 nm thick -oriented-Pb(Zr0.45Ti0.55)O-3 (PZT) thin-film capacitors through a polarization hysteresis loop and piezoelectric force microscopy (PFM) on top of the Pt electrode. Positive voltage pulses of 450 kV/cm ...
The present paper proposes a model of relaxer ferroelectrics, which describes the polarization response of these materials in terms of vibration of the interphase boundary between the polar regions and nonpolar matrix. The model is formulated and is applie ...