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Full-Text Articles in Physics
Peritubular Dentin Lacks Piezoelectricity, S. Habelitz, B. J. Rodriguez, S. J. Marshall, G. W. Marshall, Sergei V. Kalinin, Alexei Gruverman
Peritubular Dentin Lacks Piezoelectricity, S. Habelitz, B. J. Rodriguez, S. J. Marshall, G. W. Marshall, Sergei V. Kalinin, Alexei Gruverman
Alexei Gruverman Publications
Dentin is a mesenchymal tissue, and, as such, is based on a collagenous matrix that is reinforced by apatite mineral. Collagen fibrils show piezoelectricity, a phenomenon that is used by piezoresponse force microscopy (PFM) to obtain high-resolution images. We applied PFM to image human dentin with 10-nm resolution, and to test the hypothesis that zones of piezoactivity, indicating the presence of collagen fibrils, can be distinguished in dentin. Piezoelectricity was observed by PFM in the dentin intertubular matrix, while the peritubular dentin remained without response. High-resolution imaging of chemically treated intertubular dentin attributed the piezoelectric effect to individual collagen fibrils …
Probing Intrinsic Polarization Properties In Bismuth-Layered Ferroelectric Films, Takayuki Watanabe, Hiroshi Funakubo, Minoru Osada, Hiroshi Uchida, B. J. Rodriguez, Alexei Gruverman
Probing Intrinsic Polarization Properties In Bismuth-Layered Ferroelectric Films, Takayuki Watanabe, Hiroshi Funakubo, Minoru Osada, Hiroshi Uchida, B. J. Rodriguez, Alexei Gruverman
Alexei Gruverman Publications
The authors report on an approach to establish intrinsic polarization properties in bismuth-layered ferroelectric films by piezoelectric coefficient and soft-mode spectroscopy, as well as by a direct polarization–electric field hysteresis. In epitaxially grown (Bi4−xNdx)Ti3O12 (0≤x≤0.73) films, they show that these complementary characterizations can phenomenologically and thermodynamically represent the intrinsic polarization states in (Bi4−xNdxTi3O12 films, and the intrinsic Ps of 67 μC/cm2 is estimated for pure Bi4Ti3O12, superior to 50 μC/cm2 in bulk single crystal. Their …
Electromechanical Behavior In Biological Systems At The Nanoscale, Alexei Gruverman, Brain J. Rodriguez, Sergei Kalinin
Electromechanical Behavior In Biological Systems At The Nanoscale, Alexei Gruverman, Brain J. Rodriguez, Sergei Kalinin
Alexei Gruverman Publications
Hierarchical structure of connective and calcified tissues from the macro- to nanoscale level determines the mechanical and biological functionality of biological materials and has been the focus of numerous recent studies. Further progress in this field requires development of microscopic techniques capable of probing materials properties, including local composition, crystallographic orientation, and mechanical properties on the nanometer-length scale. Here, we describe a piezoresponse force microscopy (PFM) approach to high-resolution imaging of biological systems, based on detection of the local piezoelectric response. Samples include human tooth, femoral cartilage, deer antler, and butterfly wing scales. PFM allows differentiation between organic and mineral …
Introduction Scanning Probe Microscopy Techniques For Electrical And Electromechanical Characterization, Sergei Kalinin, Alexei Gruverman
Introduction Scanning Probe Microscopy Techniques For Electrical And Electromechanical Characterization, Sergei Kalinin, Alexei Gruverman
Alexei Gruverman Publications
Progress in modem science is impossible without reliable tools for characterization of structural, physical, and chemical properties of materials and devices at the micro-, nano-, and atomic scale levels. While structural information can be obtained by such established techniques as scanning and transmission electron microscopy, high-resolution examination of local electronic structure, electric potential and chemical functionality is a much more daunting problem. Local electronic properties became accessible after the development of Scanning Tunneling Microscopy by G. Binnig and H. Rohrer in 1981 at IBM Zurich 25 years ago-an invention that earned its authors the Nobel Prize in Physics five years …
Nanoscale Characterization Of Electronic And Electrical Properties Of Iii-Nitrides By Scanning Probe Microscopy, Brian J. Rodriguez, Alexei Gruverman, Robert J. Nemanich
Nanoscale Characterization Of Electronic And Electrical Properties Of Iii-Nitrides By Scanning Probe Microscopy, Brian J. Rodriguez, Alexei Gruverman, Robert J. Nemanich
Alexei Gruverman Publications
Recent interest in the technological potential of nitride-based semiconductors has led to the development and commercialization of a wide range of electronic devices. The nanoscale investigation of the electric properties of III-nitride thin films, bulk crystals, and heterostructures is of considerable interest for determining how interfaces, defects, and inversion domain boundaries affect device performance. The pyroelectric nature of wurtzitic III-nitrides is characterized by a spontaneous polarization that exists without the presence of an external field and by a polarization-bound surface charge. Scanning probe-based measurements of surface contact potentials and surface band bending in these materials, which are of crucial importance …
Review Of Ferroelectric Domain Imaging By Piezoresponse Force Microscopy, Andrei Kholkin, Sergei Kalinin, Andreas Roelofs, Alexei Gruverman
Review Of Ferroelectric Domain Imaging By Piezoresponse Force Microscopy, Andrei Kholkin, Sergei Kalinin, Andreas Roelofs, Alexei Gruverman
Alexei Gruverman Publications
This chapter describes the principles, theoretical background, recent developments, and applications of a local probe-based technique for nondestructive highresolution ferroelectric domain imaging and manipulation-piezoresponse force microscopy (PFM). This technique has proven to be a powerful tool for the characterization of ferroelectric thin films, ceramics, and single crystals. Recent advances in application of PFM for studying a mechanism of polarization reversal at the nanoscale, domain dynamics, degradation effects, and size-dependent phenomena in ferroelectrics are reviewed in detail. Examples of using PFM for the characterization of various polar materials such as ferroelectric films, piezoelectric semiconductors, and ferroelectric relaxors are given.