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Articles 30901 - 30930 of 36659

Full-Text Articles in Physical Sciences and Mathematics

Long Base-Line Measurements Of Short Period Mesospheric Gravity Waves During The Seek Campaign, Michael J. Taylor, S. H. Seo, T. Nakamura, T. Tsuda, H. Fukunishi, Y. Takahashi Jun 1998

Long Base-Line Measurements Of Short Period Mesospheric Gravity Waves During The Seek Campaign, Michael J. Taylor, S. H. Seo, T. Nakamura, T. Tsuda, H. Fukunishi, Y. Takahashi

All Physics Faculty Publications

Simultaneous observations of short‐period (<1 hour) mesospheric gravity waves were made over an extended base‐line (∼660 km) from two sites in Japan (at Shigaraki and Yamagawa) during the SEEK (Sporadic‐E Experiment over Kyushu) campaign, 9–23 August, 1996. Coincident image data obtained on four nights provided a rare opportunity to investigate the horizontal spatial extent and propagation characteristics of the waves in detail. Surprisingly, out of a total of 12 events observed from Shigaraki and 10 from Yamagawa at most only three exhibited similar propagation characteristics at each site. The majority of the wave displays (∼70–75%) had quite dissimilar characteristics suggesting a preponderance for localized wave motions of limited lifetimes and geographical extent. A marked preference for wave progression towards the N‐NE indicates that the gravity waves imaged in the near infrared OH and OI (557.7 nm) nightglow emissions were probably not directly associated with the observed E‐region irregularities.

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Observation Of Oscillations Between Degenerate Bound-State Configurations In Rapidly Autoionizing Two-Electron Atoms, M. B. Campbell, Thomas J. Bensky, Robert R. Jones Jun 1998

Observation Of Oscillations Between Degenerate Bound-State Configurations In Rapidly Autoionizing Two-Electron Atoms, M. B. Campbell, Thomas J. Bensky, Robert R. Jones

Physics

The oscillation between bound-state configurations in a rapidly autoionizing three-body Coulomb system has been directly observed. Using a 500-fsec laser pulse, calcium atoms are excited to the pure 4p3/215d two-electron configuration at an energy greater than 3 eV above the ionization limit. As a result of configuration interaction, the electrons scatter coherently into multiple bound and continuum configurations. The oscillation between the degenerate 4p1/2n′d and 4p3/2nd modes as well as autoionization into 4s1/2εl, 3d3/2εl, and 3d5/2εl …

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Translational Diffusion Of Small And Large Mesoscopic Probes In Hydroxypropylcellulose-Water In The Solutionlike Regime, Kiril A. Streletzky, George D.J. Phillies Jun 1998

Translational Diffusion Of Small And Large Mesoscopic Probes In Hydroxypropylcellulose-Water In The Solutionlike Regime, Kiril A. Streletzky, George D.J. Phillies

Physics Faculty Publications

Quasi-elastic light scattering spectroscopy was used to study the translational diffusion of monodisperse spheres in aqueous 1 MDa hydroxypropylcellulose (HPC) at 25 °C. Probe diameters d spanned 14–455 nm; HPC concentrations were 0⩽c⩽7g/L. Light scattering spectroscopy consistently found spectra having the form g(1)(t)=(1−Af)exp(−θtβ)+Af exp(−θftβf). Here θf and βf refer to the “fast” mode; θ and β describe the “slow” mode. We examine the dependence of θ, β, θf, βf, and Af on d, c, scattering vector q, and viscosity η. β=1 for large probes; elsewise, β and βf are ∈(0,1). The slow mode, with short-lived memory function, is diffusive; for …

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Dynamically Maintained Steady-State Pressure Gradients, D. P. Sheehan Jun 1998

Dynamically Maintained Steady-State Pressure Gradients, D. P. Sheehan

Physics and Biophysics: Faculty Scholarship

In a sealed blackbody cavity with gas, pressure gradients commonly take three forms: (a) statistical fluctuations, (b) transients associated with the system relaxing toward equilibrium, and (c)equilibrium pressure gradients associated with potential gradients (such as with gravity). In this paper, it is shown that in the low-density (collisionless) regime, a fourth type of pressure gradient may arise, this due to steady-state differential thermal desorption of surface species from chemically active surfaces. This gas phase is inherently nonequilibrium in character. Numerical simulations using realistic physical parameters support the possibility of this gas phase and indicate that these novel pressure gradients might …

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Four Paradoxes Involving The Second Law Of Thermodynamics, D. P. Sheehan Jun 1998

Four Paradoxes Involving The Second Law Of Thermodynamics, D. P. Sheehan

Physics and Biophysics: Faculty Scholarship

Recently four independent paradoxes have been proposed which appear to challenge the second law of thermodynamics [1-8]. These paradoxes are briefly reviewed. It is shown that each paradox results from a synergism of two broken symmetries - one geometric, one thermodynamic

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Electron Emission Following The Interaction Of Slow Highly Charged Ions With Solids, Joseph W. Mcdonald Jun 1998

Electron Emission Following The Interaction Of Slow Highly Charged Ions With Solids, Joseph W. Mcdonald

Dissertations

The interaction of highly-charged ions with surfaces involves many excitation processes of the surface atoms and the bulk material. One such process, the emission of electrons from surfaces due to the potential energy of the incident ions has been studied. The experimental results presented here confirm that the majority of electrons emitted as a result of highly-charged ions interacting with a solid surface have energies of about 20 eV. Auger processes contribute a smaller fraction of the total emitted electrons with increasing Z o f the projectile. This contribution to the total electron emission yield is found to be less …

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Scaled-Energy Floquet Spectroscopy In A Strong Electric Field: A Semiquantal Calculation Of The Recurrence Spectrum, V. Kondratovich, John B. Delos Jun 1998

Scaled-Energy Floquet Spectroscopy In A Strong Electric Field: A Semiquantal Calculation Of The Recurrence Spectrum, V. Kondratovich, John B. Delos

Arts & Sciences Articles

We consider a hydrogen atom in a strong static electric field with a weak parallel radio-frequency (rf) field. We compute the photoabsorption spectrum by calculating the spectrum of Floquet states, including their quasienergies and their oscillator strengths. Our calculation is based upon “semiquantal” formulas: we calculate the discrete spectrum of quasienergy states by using a quantum adiabatic approximation combined with semiclassical (Bohr-Sommerfeld) quantization rules. We express this spectrum in a manner consistent with the method of scaled-variable spectroscopy, and then calculate the Fourier transform. These calculated absorption spectra and recurrence spectra are in good agreement with experiments on Li atoms. …

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Search For A New Gauge Boson In Π0 Decays, Nomad Collaboration, J. Altegoer, D. Autiero, A. Baldisseri, M. Baldo-Ceolin, G. Ballocchi, M. Banner, S. Basa, G. Bassompierre, K. Benslama, N. Besson, I. Bird, B. Blumenfeld, F. Bobisut, J. Bouchez, S. Boyd, A. Bueno, S. Bunyatov, L. Camilleri, K. Zuber, Roberto Petti, Et. Al. May 1998

Search For A New Gauge Boson In Π0 Decays, Nomad Collaboration, J. Altegoer, D. Autiero, A. Baldisseri, M. Baldo-Ceolin, G. Ballocchi, M. Banner, S. Basa, G. Bassompierre, K. Benslama, N. Besson, I. Bird, B. Blumenfeld, F. Bobisut, J. Bouchez, S. Boyd, A. Bueno, S. Bunyatov, L. Camilleri, K. Zuber, Roberto Petti, Et. Al.

Faculty Publications

A search was made for a new light gauge boson X which might be produced in π0→γ+X decay from neutral pions generated by 450 GeV protons in the CERN SPS neutrino target. The X's would penetrate the downstream shielding and be observed in the NOMAD detector via the Primakoff effect, in the process of X→π0 conversion in the external Coulomb field of a nucleus. With 1.45×1018 protons on target, 20 candidate events with energy between 8 and 140 GeV were found from the analysis of neutrino data. This number is in …

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Pressure Ionization And Line Merging In Strongly Coupled Plasmas Produced By 100-Fs Laser Pulses, M. Nantel, G. Ma, S. Gu, C.Y. Côté, J. Itatani, Donald Umstadter May 1998

Pressure Ionization And Line Merging In Strongly Coupled Plasmas Produced By 100-Fs Laser Pulses, M. Nantel, G. Ma, S. Gu, C.Y. Côté, J. Itatani, Donald Umstadter

Donald Umstadter Publications

Time- and space-resolved extreme ultraviolet spectra of carbon plasmas, created with 100-fs laser pulses, are obtained with the novel technique of picosecond jitter-free streak-camera averaging. Spectroscopic diagnostics indicate electron densities and temperatures evolving from 1023 to 1021 cm-3 and 80 to 50 eV, respectively, implying less than one particle in a Debye sphere at early times. The emission reveals conditions of extreme pressure ionization and line merging. Comparisons of the experimental spectra with numerical simulations validate the use of the Inglis-Teller limit for line merging, and confirm that pressure ionization models based on the Debye-Huckel potential are …

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Search For Inclusive B→Sl+L-, S. Glenn, Kenneth A. Bloom, Cleo Collaboration May 1998

Search For Inclusive B→Sl+L-, S. Glenn, Kenneth A. Bloom, Cleo Collaboration

Kenneth Bloom Publications

We have searched for the effective flavor changing neutral-current decays b→sl+l- using an inclusive method. We set upper limits on the branching ratios B(b→ se+e-) < 5.7 X 10-5, B(b→ sμ+μ-) < 5.8 X 10-5 and Bb→se+μ-) < 2.2 3 10-5 [at 90% confidence level (C.L.)]. Combing the dielectron and dimuon decay modes we find b→sl+l-) < 4.2 X 10-5 (at 90% C.L.).

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Orthogonal Polynomial Projectors For The Projector Augmented Wave Method Of Electronic Structure Calculations, N. A. W. Holzwarth, G. E. Matthews, A. R. Tackett, Rodney Dunning May 1998

Orthogonal Polynomial Projectors For The Projector Augmented Wave Method Of Electronic Structure Calculations, N. A. W. Holzwarth, G. E. Matthews, A. R. Tackett, Rodney Dunning

Chemistry & Physics Faculty Publications

The projector augmented wave (PAW) method for electronic structure calculations developed by Blochl [Phys. Rev. B 50, 17 953 (1994)] has been very successfully used for density functional studies. It has the numerical advantages of pseudopotential techniques while retaining the physics of all-electron formalisms. We describe a method for generating the set of atom-centered projector and basis functions that are needed for the PAW method. This scheme chooses the shapes of the projector functions from a set of orthogonal polynomials multiplied by a localizing weight factor. Numerical benefits of the scheme result from having direct control of the …

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Particulate Sizing And Emission Indices For A Jet Engine Exhaust Sampled At Cruise, Donald E. Hagen, Philip D. Whitefield, J. Paladino, Max B. Trueblood, H. Lilenfeld May 1998

Particulate Sizing And Emission Indices For A Jet Engine Exhaust Sampled At Cruise, Donald E. Hagen, Philip D. Whitefield, J. Paladino, Max B. Trueblood, H. Lilenfeld

Physics Faculty Research & Creative Works

Particle size and emission indices measurements for jet engines, primarily the Rolls Royce RB211 engines on a NASA 757 aircraft are reported. These data were used to estimate the fraction of fuel sulfur that was converted to particulates. These measurements were made in-situ with the sampling aircraft several kilometers behind the source. Some complimentary ground measurements on the same source aircraft and engines are also reported. Significant differences are seen between the ground observations and the in-situ observations, indicating that plume processes are changing the aerosol' s characteristics.

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Polydispersivity Of Non-Critical Field-Induced Fluctuations In Febr2, Christian Binek May 1998

Polydispersivity Of Non-Critical Field-Induced Fluctuations In Febr2, Christian Binek

Christian Binek Publications

The field and temperature dependence of the complex low-frequency susceptibility of the metamagnet FeBr2 exhibits large anomalies in the vicinity of the second-order phase boundary Hc(T). The low-frequency losses reflect polydispersive dynamics with a broad distribution of relaxation times peaking at τ ≈ 0.2 s. The dispersion, χ versus ƒ, is well described within Chamberlin's model of dynamically coupled domains. The heterogeneous glass-like response gives rise to the intuitive picture of a magnetic fluid of high viscosity.

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Shape Invariance And Its Connection To Potential Algebra, Asim Gangopadhyaya, Jeffrey Mallow, Uday P. Sukhatme May 1998

Shape Invariance And Its Connection To Potential Algebra, Asim Gangopadhyaya, Jeffrey Mallow, Uday P. Sukhatme

Physics: Faculty Publications and Other Works

Exactly solvable potentials of nonrelativistic quantum mechanics are known to be shape invariant. For these potentials, eigenvalues and eigenvectors can be derived using well known methods of supersymmetric quantum mechanics. The majority of these potentials have also been shown to possess a potential algebra, and hence are also solvable by group theoretical techniques. In this paper, for a subset of solvable problems, we establish a connection between the two methods and show that they are indeed equivalent.

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Resistivity Of Boron-Doped Diamond Microcrystals, M. D. Jaeger, S. Hyun, Anthony Roy Day, M. F. Thorpe, B. Golding May 1998

Resistivity Of Boron-Doped Diamond Microcrystals, M. D. Jaeger, S. Hyun, Anthony Roy Day, M. F. Thorpe, B. Golding

Anthony Roy Day

We describe measurements of the electrical resistivity of micron-size crystallites of boron-doped diamond. Electron-beam lithography was employed for writing sample-specific contacts on small, well-faceted diamond crystals grown by chemical-vapor deposition on silicon substrates. After generating a three-dimensional computer model of the crystallite, a finite-element analysis was used to calculate the internal electrostatic potential distribution. Multiterminal resistance measurements, in conjunction with a computed geometrical factor, enabled the absolute resistivity to be determined. We find that the resistivities obtained from two different crystallites agree to better than 10%. The results are compared with transport measurements on a large-area homoepitaxial diamond film grown …

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Reaction Sequence Of Iron Sulfide Minerals In Bacteria And Their Use As Biomarkers, Mihály Pósfai, Peter R. Buseck, D. A. Bazylinski, Richard B. Frankel May 1998

Reaction Sequence Of Iron Sulfide Minerals In Bacteria And Their Use As Biomarkers, Mihály Pósfai, Peter R. Buseck, D. A. Bazylinski, Richard B. Frankel

Physics

Some bacteria form intracellular nanometer-scale crystals of greigite (Fe3S4) that cause the bacteria to be oriented in magnetic fields. Transmission electron microscope observations showed that ferrimagnetic greigite in these bacteria forms from nonmagnetic mackinawite (tetragonal FeS) and possibly from cubic FeS. These precursors apparently transform into greigite by rearrangement of iron atoms over a period of days to weeks. Neither pyrrhotite nor pyrite was found. These results have implications for the interpretation of the presence of pyrrhotite and greigite in the martian meteorite ALH84001.

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Radial Dependence Of The Nucleon Effective Mass In 10b, L J. De Bever, R S. Hicks, R A. Miskimen, Gerald Alvin Peterson May 1998

Radial Dependence Of The Nucleon Effective Mass In 10b, L J. De Bever, R S. Hicks, R A. Miskimen, Gerald Alvin Peterson

Gerald Alvin Peterson

The dynamic properties of the atomic nucleus depend strongly on correlations between the nucleons. We present a combined analysis of inelastic electron-scattering data and electron-induced proton knockout measurements in an effort to obtain phenomenological information on nucleon-nucleon correlations. Our results indicate that the ratio of radial wave functions extracted from precise 10B(e,e′) and 10B(e,e′p) measurements evolve from an interior depression for small Em, characteristic of short-range correlations, to a surface-peaked enhancement for larger Em, characteristic of long-range correlations. This observation can be interpreted in terms of the nucleon effective mass.

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Observation Of The Radiative Decay D*+→D+Γ, J. Bartelt, Kenneth A. Bloom, Cleo Collaboration May 1998

Observation Of The Radiative Decay D*+→D+Γ, J. Bartelt, Kenneth A. Bloom, Cleo Collaboration

Kenneth Bloom Publications

We have observed a signal for the decay D*+→D+γ at a significance of 4 standard deviations. From the measured branching ratio B(D*+→D+γ)/ B(D*+→ D++pi0 = 0.055 ± 0.014 ± 0.010 we find B(D*+→D+γ)= 0.017 ± 0.004 ± 0.003, where the first uncertainty is statistical and the second is systematic. We also report the highest precision determination of the remaining D*+ branching fractions.

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Known Source Detection Predictions For Higher Order Correlators, Lisa A. Pflug, George E. Ioup, Juliette W. Ioup May 1998

Known Source Detection Predictions For Higher Order Correlators, Lisa A. Pflug, George E. Ioup, Juliette W. Ioup

Physics Faculty Publications

The problem addressed in this paper is whether higher order correlation detectors can perform better in white noise than the cross correlation detector for the detection of a known transient source signal, if additional receiver information is included in the higher order correlations. While the cross correlation is the optimal linear detector for white noise, additional receiver information in the higher order correlations makes them nonlinear. In this paper, formulas that predict the performance of higher order correlation detectors of energy signals are derived for a known source signal. Given the first through fourth order signal moments and the noise …

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Measuring The Bunch-Length Of An Electron Beam By Utilizing The Laser Heterodyne Technique, Katrina L. Carter May 1998

Measuring The Bunch-Length Of An Electron Beam By Utilizing The Laser Heterodyne Technique, Katrina L. Carter

Electronic Dissertations and Theses

The focus of this project was to develop an apparatus that would aid in measuring the bunch-length of an electron beam at the interaction point of the Stanford Linear Collider (SLC) by utilizing the laser heterodyne technique. This technique involves the superposition of two laser pulses of slightly different frequencies. As a result, a traveling fringe pattern is created, and a bunch-to-bunch variation of the Compton rate would be introduced. The magnitude of this variation depends on the best wavelength and on Fourier transform of the longitudinal bunch distribution. The laser heterodyne technique is implemented by the addition of a …

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Search For Color-Suppressed B Hadronic Decay Processes At The Υ(4S) Resonance, B. Nemati, Kenneth A. Bloom, Cleo Collaboration May 1998

Search For Color-Suppressed B Hadronic Decay Processes At The Υ(4S) Resonance, B. Nemati, Kenneth A. Bloom, Cleo Collaboration

Kenneth Bloom Publications

Using 3.1 fb-1 of data accumulated at the Υ(4S) by the CLEO-II detector, corresponding to 3.3×106 BB̅ pairs, we have searched for the color-suppressed B hadronic decay processes B0→D0 (D*0)X0, where X0 is a light neutral meson π0, ρ0, η, η′ or ω. The D*0 mesons are reconstructed in D*0→D0π0 and the D0 mesons in D0→K-π+, K-π+π0 and K …

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New Limits For Neutrinoless Tau Decays, D. W. Bliss, Kenneth A. Bloom, Cleo Collaboration May 1998

New Limits For Neutrinoless Tau Decays, D. W. Bliss, Kenneth A. Bloom, Cleo Collaboration

Kenneth Bloom Publications

Neutrinoless 3-prong tau lepton decays into a charged lepton and either two charged particles or one neutral meson have been searched for using 4.79 fb-1 of data collected with the CLEO II detector at Cornell Electron Storage Ring. This analysis represents an update of a previous study and the addition of six decay channels. In all channels the numbers of events found are compatible with background estimates and branching fraction upper limits are set for 28 different decay modes. These limits are either more stringent than those set previously or represent the first attempt to find these decays.

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Field-Induced Transverse Spin Ordering In Febr2, O. Petracie, Christian Binek, Wolfgang Kleemann, U. Neuhausen, H. Lueken May 1998

Field-Induced Transverse Spin Ordering In Febr2, O. Petracie, Christian Binek, Wolfgang Kleemann, U. Neuhausen, H. Lueken

Christian Binek Publications

Weak first-order phase transitions from axial to oblique spin ordering in FeBr2 are evidenced by superconducting quantum interference device magnetometry in axial fields H1(T) above the multicritical point, Hm=2.4 MA/m, Tm=4.6 K, and below the antiferro-to-paramagnetic phase line, Hc (T), in agreement with recent specific-heat data [H. Aruga Katori, K. Katsumata, and M. Katori, Phys. Rev. B 54, R9620 (1996)]. The ordering of the in-plane moments is probably due to nondiagonal coupling to the longitudinal ones, both of which increase discontinuously at H1 (T) only under …

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High Mobility Algan/Gan Heterostructures Grown By Gas-Source Molecular Beam Epitaxy, L. K. Li, J. Alperin, W. I. Wang, David C. Look, Donald C. Reynolds May 1998

High Mobility Algan/Gan Heterostructures Grown By Gas-Source Molecular Beam Epitaxy, L. K. Li, J. Alperin, W. I. Wang, David C. Look, Donald C. Reynolds

Physics Faculty Publications

We report on the growth of high electron mobility AlGaN/GaN heterostructures on sapphire substrates by gas-source molecular beam epitaxy (GSMBE) using ammonia as the nitrogen source. Improvements in structural, electrical, and optical properties of GaN and AlGaN layers have been made to achieve this goal. For the growth of AlGaN layers, the reflection high-energy electron diffraction revealed a twofold surface reconstruction, indicative of atomic smoothness of the film surface. High mobility two-dimensional electron gas has been achieved in both unintentionally doped (by piezoelectric effect induced by lattice mismatch strain) and modulation doped AlGaN/GaN heterostructures. The modulation-doped n+-Al0.2Ga …

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Neutral-Donor-Bound-Exciton Complexes In Zno Crystals, D. C. Reynolds, David C. Look, B. Jogai, C. W. Litton, T. C. Collins, W. C. Harsch, G. Cantwell May 1998

Neutral-Donor-Bound-Exciton Complexes In Zno Crystals, D. C. Reynolds, David C. Look, B. Jogai, C. W. Litton, T. C. Collins, W. C. Harsch, G. Cantwell

Physics Faculty Publications

Neutral-donor–bound-exciton transitions have been observed in ZnO. The isolated neutral donors are made up of defect pair complexes. The neutral-donor nature of these pair complexes was determined from magneticfield measurements and from two-electron transitions. Excited states of the neutral-donor bound excitons were observed in the form of rotator states analogous to rotational states of the H2 molecule.

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Nobel Prize Winners In Physics From 1901 To 1990: Simple Statistics For Physics Teachers, Weijia Zhang, Robert Fuller May 1998

Nobel Prize Winners In Physics From 1901 To 1990: Simple Statistics For Physics Teachers, Weijia Zhang, Robert Fuller

Robert G. Fuller Publications

A demographic database for the 139 Nobel prize winners in physics from 1901 to 1990 has been created from a variety of sources. The results of our statistical study are discussed in the light of the implications for physics teaching.

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Particulate Sizing And Emission Indices For A Jet Engine Exhaust Sampled At Cruise, Donald E. Hagen, Philip D. Whitefield, Jonathan D. Paladino, Max B. Trueblood May 1998

Particulate Sizing And Emission Indices For A Jet Engine Exhaust Sampled At Cruise, Donald E. Hagen, Philip D. Whitefield, Jonathan D. Paladino, Max B. Trueblood

Physics Faculty Research & Creative Works

Particle size and emission indices measurements for jet engines, primarily the Rolls Royce RB211 engines on a NASA 757 aircraft are reported. These data were used to estimate the fraction of fuel sulfur that was converted to particulates. These measurements were made in-situ with the sampling aircraft several kilometers behind the source. Some complimentary ground measurements on the same source aircraft and engines are also reported. Significant differences are seen between the ground observations and the in-situ observations, indicating that plume processes are changing the aerosol's characteristics.

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Sources And Chemistry Of Noₓ In The Upper Troposphere Over The United States, Lyatt Jaegle, Daniel J. Jacob, Yuhua Wang, Andrew J. Weinheimer, Brian A. Ridley, Teresa L. Campos, Glen W. Sachse, Donald E. Hagen May 1998

Sources And Chemistry Of Noₓ In The Upper Troposphere Over The United States, Lyatt Jaegle, Daniel J. Jacob, Yuhua Wang, Andrew J. Weinheimer, Brian A. Ridley, Teresa L. Campos, Glen W. Sachse, Donald E. Hagen

Physics Faculty Research & Creative Works

The origin of NOx in the upper troposphere over the central United States is examined using aircraft observations obtained during the SUCCESS campaign in April–May of 1996. Correlations between NOy (sum of NOx and its oxidation products) and CO at 8–12 km altitude indicate that NOx originates primarily from convective transport of polluted boundary layer air. Lightning and aircraft emissions appear to be only minor sources of NOx. Chemical steady state model calculations constrained by local observations of NO underestimate the measured NOx/NOy concentration ratio at 8–12 km altitude by a …

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The Growth Of Strained Thin Films Of Gadolinium, C. Waldfried, O. Zeybek, T. Bertrams, S.C. Barrett, Peter A. Dowben May 1998

The Growth Of Strained Thin Films Of Gadolinium, C. Waldfried, O. Zeybek, T. Bertrams, S.C. Barrett, Peter A. Dowben

Peter Dowben Publications

The growth of strained thin films of gadolinium has been investigated with low-energy electron diffraction (LEED) and scanning tunneling microscopy (STM) and compared to the film growth of unstrained gadolinium. Strained thin films of gadolinium are distinct from the unstrained films by a substrate induced preferential domain growth direction, which is also reflected in the electronic structure.

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The Spin Polarized Band Structure Of Strained Thin Films Of Gadolinium, C. Waldfried, Elio Vescovo, Peter A. Dowben May 1998

The Spin Polarized Band Structure Of Strained Thin Films Of Gadolinium, C. Waldfried, Elio Vescovo, Peter A. Dowben

Peter Dowben Publications

The magnetic properties of strained thin films of gadolinium are characterized by a wave vector and thickness dependence of the exchange splitting. The spin-resolved band structure has been mapped by spin polarized photoemission, and provides considerable insight into the relationship between magnetism of local moment systems, and band structure.

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