Trelenberg TW, Fatema R, Li JA, Akhadov EA, Van Winkle DH, Skofronick JG, Safron SA, Flaherty FA, Boatner LA. Surface structure of niobium-doped potassium tantalate KTa(1-x)Nb(x)O3 obtained from helium atom scattering studies.
JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2010;
22:304009. [PMID:
21399341 DOI:
10.1088/0953-8984/22/30/304009]
[Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
Helium atom scattering experiments have been carried out on the (001) surface of KTaO(3) doped with 6, 10 and 15% Nb, produced by cleaving in situ single crystal samples. Several phenomena were observed through He atom diffraction measurements, including metastable behavior immediately after cleaving, reconstruction of a fraction of the surface to (2 × 1) domains after thermally cycling the surface temperatures, and the distribution of step heights of terraces at the surface as multiples of the unit cell dimension of ∼ 4 Å. In addition, a large hysteresis effect was found in the (100) azimuth in the variation of surface reflectivity with surface temperature; a much smaller hysteresis effect was found in the (110) azimuth. The hysteresis effects appear for all Nb doping concentrations. Finally, small oscillations in the specular and Bragg diffraction intensities near the surface temperature 80 K were also observed.
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