The Experts below are selected from a list of 72708 Experts worldwide ranked by ideXlab platform
Shriram Ramanathan - One of the best experts on this subject based on the ideXlab platform.
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hall Carrier Density and magnetoresistance measurements in thin film vanadium dioxide across the metal insulator transition
Physical Review B, 2009Co-Authors: Dmitry Ruzmetov, D Heiman, Bruce B Claflin, V Narayanamurti, Shriram RamanathanAbstract:Temperature dependent magneto-transport measurements in magnetic fields of up to 12 Tesla were performed on thin film vanadium dioxide (VO2) across the metal-insulator transition (MIT). The Hall Carrier Density increases by 4 orders of magnitude at the MIT and accounts almost entirely for the resistance change. The Hall mobility varies little across the MIT and remains low, ~0.1cm 2 /V sec. Electrons are found to be the major
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hall Carrier Density and magnetoresistance measurements in thin film vanadium dioxide across the metal insulator transition
Physical Review B, 2009Co-Authors: Dmitry Ruzmetov, D Heiman, Bruce B Claflin, V Narayanamurti, Shriram RamanathanAbstract:Temperature-dependent magnetotransport measurements in magnetic fields of up to 12 T were performed on thin-film vanadium dioxide (VO 2 ) across the metal-insulator transition (MIT). The Hall Carrier Density increases by 4 orders of magnitude at the MIT and accounts almost entirely for the resistance change. The Hall mobility varies little across the MIT and remains low, ~0.1 cm 2 /V sec. Electrons are found to be the major Carriers on both sides of the MIT. Small positive magnetoresistance in the semiconducting phase is measured.
Andreas Mandelis - One of the best experts on this subject based on the ideXlab platform.
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Carrier Density wave transport property depth profilometry using spectroscopic photothermal radiometry of silicon wafers ii experimental and computational aspects
Journal of Applied Physics, 2003Co-Authors: Derrick Shaughnessy, Andreas MandelisAbstract:The experimental verification of a previously presented theoretical model for the photothermal radiometric (PTR) signal from an Si wafer excited by a laser of arbitrary wavelength is presented. A multiparameter fitting algorithm is developed and is used to fit experimental frequency scans to the theoretical model. The recombination lifetime and surface recombination velocity values extracted from the fits are consistent for all of the experiments performed. The diffusion coefficients for the more strongly absorbed excitation wavelengths are greater than those measured when using deeper penetrating excitation wavelengths. This discrepancy is discussed in terms of the dependence of the PTR signal on injected Carrier densities and the nonlinearity of the PTR signal with temperature. The sensitivity of the PTR signal to a localized defect is shown to increase with the proximity of the defect to the centroid of the injected Carrier Density. The method amounts to Carrier-Density-wave depth profilometry of the r...
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Carrier Density wave transport property depth profilometry using spectroscopic photothermal radiometry of silicon wafers i theoretical aspects
Journal of Applied Physics, 2003Co-Authors: Derrick Shaughnessy, Andreas MandelisAbstract:A theoretical model for the photothermal radiometric (PTR) signal from an indirect band-gap semiconductor excited by a laser of arbitrary wavelength is presented. The model has been used to investigate the spectral dependence of the sensitivity of the PTR signal to variations in the electronic transport parameters of the sample. Simulations show slight variations of the sensitivity to Carrier lifetime and Carrier diffusivity with excitation wavelength due to changes in the strength of the thermal contribution to the signal that are a result of changes in the difference between the photon energy and the band gap. The sensitivity of the PTR signal to changes in the front surface recombination velocity is shown to have a strong dependence on the excitation wavelength with the sensitivity decreasing as the absorption depth of the excitation source increases, allowing spectroscopic Carrier-Density-wave depth profilometric measurements.
Dmitry Ruzmetov - One of the best experts on this subject based on the ideXlab platform.
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hall Carrier Density and magnetoresistance measurements in thin film vanadium dioxide across the metal insulator transition
Physical Review B, 2009Co-Authors: Dmitry Ruzmetov, D Heiman, Bruce B Claflin, V Narayanamurti, Shriram RamanathanAbstract:Temperature dependent magneto-transport measurements in magnetic fields of up to 12 Tesla were performed on thin film vanadium dioxide (VO2) across the metal-insulator transition (MIT). The Hall Carrier Density increases by 4 orders of magnitude at the MIT and accounts almost entirely for the resistance change. The Hall mobility varies little across the MIT and remains low, ~0.1cm 2 /V sec. Electrons are found to be the major
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hall Carrier Density and magnetoresistance measurements in thin film vanadium dioxide across the metal insulator transition
Physical Review B, 2009Co-Authors: Dmitry Ruzmetov, D Heiman, Bruce B Claflin, V Narayanamurti, Shriram RamanathanAbstract:Temperature-dependent magnetotransport measurements in magnetic fields of up to 12 T were performed on thin-film vanadium dioxide (VO 2 ) across the metal-insulator transition (MIT). The Hall Carrier Density increases by 4 orders of magnitude at the MIT and accounts almost entirely for the resistance change. The Hall mobility varies little across the MIT and remains low, ~0.1 cm 2 /V sec. Electrons are found to be the major Carriers on both sides of the MIT. Small positive magnetoresistance in the semiconducting phase is measured.
Derrick Shaughnessy - One of the best experts on this subject based on the ideXlab platform.
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Carrier Density wave transport property depth profilometry using spectroscopic photothermal radiometry of silicon wafers ii experimental and computational aspects
Journal of Applied Physics, 2003Co-Authors: Derrick Shaughnessy, Andreas MandelisAbstract:The experimental verification of a previously presented theoretical model for the photothermal radiometric (PTR) signal from an Si wafer excited by a laser of arbitrary wavelength is presented. A multiparameter fitting algorithm is developed and is used to fit experimental frequency scans to the theoretical model. The recombination lifetime and surface recombination velocity values extracted from the fits are consistent for all of the experiments performed. The diffusion coefficients for the more strongly absorbed excitation wavelengths are greater than those measured when using deeper penetrating excitation wavelengths. This discrepancy is discussed in terms of the dependence of the PTR signal on injected Carrier densities and the nonlinearity of the PTR signal with temperature. The sensitivity of the PTR signal to a localized defect is shown to increase with the proximity of the defect to the centroid of the injected Carrier Density. The method amounts to Carrier-Density-wave depth profilometry of the r...
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Carrier Density wave transport property depth profilometry using spectroscopic photothermal radiometry of silicon wafers i theoretical aspects
Journal of Applied Physics, 2003Co-Authors: Derrick Shaughnessy, Andreas MandelisAbstract:A theoretical model for the photothermal radiometric (PTR) signal from an indirect band-gap semiconductor excited by a laser of arbitrary wavelength is presented. The model has been used to investigate the spectral dependence of the sensitivity of the PTR signal to variations in the electronic transport parameters of the sample. Simulations show slight variations of the sensitivity to Carrier lifetime and Carrier diffusivity with excitation wavelength due to changes in the strength of the thermal contribution to the signal that are a result of changes in the difference between the photon energy and the band gap. The sensitivity of the PTR signal to changes in the front surface recombination velocity is shown to have a strong dependence on the excitation wavelength with the sensitivity decreasing as the absorption depth of the excitation source increases, allowing spectroscopic Carrier-Density-wave depth profilometric measurements.
Yoshihiro Iwasa - One of the best experts on this subject based on the ideXlab platform.
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Accessing the transport properties of graphene and its multilayers at high Carrier Density
Proceedings of the National Academy of Sciences of the United States of America, 2011Co-Authors: J. Ye, Masanori Koshino, H. Shimotani, S. Russo, H Yuan, Alberto F Morpurgo, S Inoue, Monica F Craciun, Yoshihiro IwasaAbstract:We present a comparative study of high Carrier Density transport in mono-, bi-, and trilayer graphene using electric double-layer transistors to continuously tune the Carrier Density up to values exceeding 10(14) cm(-2). Whereas in monolayer the conductivity saturates, in bi- and trilayer filling of the higher-energy bands is observed to cause a nonmonotonic behavior of the conductivity and a large increase in the quantum capacitance. These systematic trends not only show how the intrinsic high-Density transport properties of graphene can be accessed by field effect, but also demonstrate the robustness of ion-gated graphene, which is crucial for possible future applications.