We have determined the electron-coupling spectrum of superconducting Bi2Sr2CaCu2O(8+δ) from high-resolution angle-resolved photoemission spectra by two deconvolution-free robust methods. As hole concentration decreases, the coupling spectral weight at low energies ≲15  meV shows a twofold and nearly band-independent enhancement, while that around ∼65  meV increases moderately, and that in ≳130  meV decreases leading to a crossover of dominant coupling excitation between them. Our results suggest the competition among multiple screening effects, and provide important clues to the source of sufficiently strong low-energy coupling, λ(LE)≈1, in an underdoped system.

SrRuO3 films were grown on (001)SrTiO3 single crystal substrates by rf magnetron sputtering under various total pressures, and their crystal structure, room temperature resistivity, and temperature dependency of resistivity were investigated. High-resolution X-ray diffraction (XRD) analysis revealed that the unit cell volume of these films decreased with increasing total pressure from 1.3 to 27 Pa and was almost constant above 27 Pa corresponding to that of bulk SrRuO3. SrRuO3 films deposited under a total pressure of 27 Pa showed the lowest room temperature resistivity, i.e., 250 µΩ·cm, almost the same as the reported one of the SrRuO3 single crystal. This film also showed a positive temperature dependency of resistivity with a temperature dependency change at about 150 K, which was also in good agreement with the reported one of the SrRuO3 single crystal.

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Surface wave operation mode of the slot antenna microwave plasma source SLAN

Lead zirconate titanate, Pb(Zr,Ti)O3 or PZT, is one of the most widely investigated ferroelectric and piezoelectric materials due to its superior properties. However, the intrinsic properties of PZT have not been directly measured due to the lack of fabrication of single crystals even though a basic understanding of intrinsic properties has been of interest developing lead-free piezoelectric materials. We demonstrated the direct observation of the intrinsic piezoelectric property by means of the detection of electric-field induced crystal lattice distortion of thick Pb(Zr0.35Ti0.65)O3 single-crystalline films with single polar-axis orientation and negligible residual strain using the time-resolved X-ray diffraction (XRD) together with the polarization response. Consequently, the effective converse piezoelectric response was experimentally revealed; hence, the electrostrictive coefficient, which is the conversion coefficient between the electrical and mechanical response, was determined. The obtained effective electrostrictive coefficient was 5.2–6.3 × 10−2 m4/C2, which agrees with theoretical prediction.