Martin R. Castell

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Many microscopic investigations of materials may benefit from the recording of multiple successive images. This can include techniques common to several types of microscopy such as frame averaging to improve signal-to-noise ratios (SNR) or time series to study dynamic processes or more specific applications. In the scanning transmission electron microscope,(More)
There is growing interest in ternary oxide surfaces due to their role in areas ranging from substrates for low power electronics to heterogeneous catalysis. Descriptions of these surfaces to date focus on low-temperature explanations where enthalpy dominates, and less on the implications of configurational entropy at high temperatures. We report here the(More)
Processing the SrTiO(3)(001) surface results in the self-assembly of reduced titanate nanowires whose widths are approximately 1 nm. We have imaged these nanowires and their defects at elevated temperatures by atomic resolution scanning tunneling microscopy. The nanowire structure is modeled with density functional theory, and defects observed in the center(More)
The temperature-dependent structure transition of supported Cu nanocrystals on SrTiO3(001)-(2 x 1) is investigated by scanning tunneling microscopy (STM). We experimentally determine the phase map of supported Cu icosahedral, decahedral, and truncated octahedral nanocrystal shapes as a function of substrate temperature during Cu deposition. We show that a(More)
The structure of nanometer-sized strained Ge islands epitaxially grown on a Si substrate was studied using ultrasonic force microscopy (UFM), which combines the sensitivity to elastic structure of acoustic microscopy with the nanoscale spatial resolution of atomic force microscopy. UFM not only images the local surface elasticity variations between the Ge(More)
The ability to select the way in which atoms and molecules self-organize on a surface is important for synthesizing nanometre scale devices. Here we show how endohedral fullerenes (Er(3)N@C(80)) can be assembled into four distinctive arrangements on a strontium titanate surface template. Each template pattern correlates to a particular reconstruction on(More)
A class of nanostructured surface phases on SrTiO3(001) is reported and characterized through atomic-resolution scanning tunneling microscopy and Auger electron spectroscopy. These surface phases are created via argon ion sputtering and UHV annealing and form close-packed domains of highly ordered nanostructures. Depending on the type of nanostructures(More)
Strontium titanate is seeing increasing interest in fields ranging from thin-film growth to water-splitting catalysis and electronic devices. Although the surface structure and chemistry are of vital importance to many of these applications, theories about the driving forces vary widely. We report here a solution to the 3 x 1 SrTiO(3)(110) surface structure(More)