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Articles 1 - 28 of 28
Full-Text Articles in Physics
Structure And Magnetism Of Nifemngaxsn1-X (X=0, 0.25, 0.5, 0.75, 1.00) Heusler Compounds, Jace Waybright, Lee Halbritter, Bishnu Dahal, Hanyang Qian, Yung Huh, Pavel Lukashev, Parashu Kharel
Structure And Magnetism Of Nifemngaxsn1-X (X=0, 0.25, 0.5, 0.75, 1.00) Heusler Compounds, Jace Waybright, Lee Halbritter, Bishnu Dahal, Hanyang Qian, Yung Huh, Pavel Lukashev, Parashu Kharel
Faculty Publications
The crystal structure and magnetic properties of NiFeMnGaxSn1-x (x = 0, 0.25, 0.50, 0.75 and 1.00) Heusler compounds have been investigated experimentally and theoretically. The computational results suggest that NiFeMnGa0.75Sn0.25 is nearly half-metallic with a spin polarization P of 87%. The bulk samples prepared using arc-melting and annealing exhibit a high degree of Y-type order. All the investigated samples show ferromagnetic spin order with the Curie temperatures ranging from 284 K for NiFeMnGa to 408 K for NiFeMnSn. The intermediate composition NiFeMnGa0.75Sn0.25, which is predicted to be nearly half metallic, …
Out-Of-Plane Electron Transport In Finite Layer Mos2, R Holzapfel, Jake Weber, Pavel Lukashev, Andrew Stollenwerk
Out-Of-Plane Electron Transport In Finite Layer Mos2, R Holzapfel, Jake Weber, Pavel Lukashev, Andrew Stollenwerk
Faculty Publications
Ballistic electron emission microscopy (BEEM) has been used to study the processes affecting electron transport along the [0001] direction of finite layer MoS2 flakes deposited onto the surface of Au/Si(001) Schottky diodes. Prominent features present in the differential spectra from the MoS2 flakes are consistent with the density of states of finite layer MoS2 calculated using density functional theory. The ability to observe the electronic structure of the MoS2 appears to be due to the relatively smooth density of states of Si in this energy range and a substantial amount of elastic or quasi-elastic scattering along the MoS2/Au/Si(001) path. Demonstration …
Magnetic And Magnetocaloric Properties Of Co2-Xfexvga Heusler Alloys, K. Schroeder, J. Waybright, P. Kharel, W. Zhang, S. Valloppilly, J. Herran, P. Lukashev, Y. Huh, R. Skomsk, D. J. Sellmyer
Magnetic And Magnetocaloric Properties Of Co2-Xfexvga Heusler Alloys, K. Schroeder, J. Waybright, P. Kharel, W. Zhang, S. Valloppilly, J. Herran, P. Lukashev, Y. Huh, R. Skomsk, D. J. Sellmyer
Faculty Publications
The magnetic and magnetocaloric properties of iron-substituted Co2VGa alloys, Co2-xFexVGa (x = 0, 0.1, 0.15, 0.2, 0.3), were investigated. The Fe-substituted samples, prepared by arc melting, melt spinning, and annealing, crystallized in the L2(1) Heusler structure, without any secondary phases. The Curie temperature and high-field magnetization at 50 K decreased from 345 K and 44 emu/g (1.90 mu(B)/f.u.) for Co2VGa to 275 K and 39 emu/g (1.66 mu(B)/f.u.) for Co1.7Fe0.3VGa, respectively, but the maximum entropy change remained almost insensitive to Fe concentration for x 1.85Fe0.15VGa. First-principle …
In Praise Of The Catenary, Fred Behroozi
In Praise Of The Catenary, Fred Behroozi
Faculty Publications
When a chain hangs loosely from its end points, it takes the familiar form known as the catenary. Power lines, clothes lines, and chain links are familiar examples of the catenary in everyday life. Nevertheless, the subject is conspicuously absent from current introductory physics and calculus courses.1 Even in upper-level physics and math courses, the catenary equation is usually introduced as an example of hyperbolic functions or discussed as an application of the calculus of variations. We present a new derivation of the catenary equation that is suitable for introductory physics and mathematics courses.
Atomic Disorder Induced Modification Of Magnetization In Mncrval, Juliana Herran, Rishabh Dalal, Paul Gray, Parashu Kharel, Pavel Lukashev
Atomic Disorder Induced Modification Of Magnetization In Mncrval, Juliana Herran, Rishabh Dalal, Paul Gray, Parashu Kharel, Pavel Lukashev
Faculty Publications
We have investigated the physical mechanism behind magnetization reduction in a potential spingapless semiconducting compound MnCrVAl by analyzing various atomic disorder schemes. In particular, we show that depending on the degree of disorder, exchanging atomic positions between Mn/Cr and V/Al leads to reduced total magnetization due to either spin flip, or vanishing spin magnetic moments. The latter is attributed to the itinerant character of magnetism in Cr-, Mn-, and V-containing Heusler alloys, and to the frustration of antiferromagnetic exchange interactions, and is accompanied by a tetragonal distortion, but such distortion alone (i.e., in a fully ordered crystal, with no atomic …
Effect Of Fe Substitution On The Structural, Magnetic And Electron-Transport Properties Of Half-Metallic Co2tisi, Y. Yin, J. Waybright, P. Kharel, I. Tutic, J. Herran, P. Lukashev, S. Valloppilly, D. J. Sellmyer
Effect Of Fe Substitution On The Structural, Magnetic And Electron-Transport Properties Of Half-Metallic Co2tisi, Y. Yin, J. Waybright, P. Kharel, I. Tutic, J. Herran, P. Lukashev, S. Valloppilly, D. J. Sellmyer
Faculty Publications
The structural, magnetic and electron-transport properties of Co2Ti1-xFexSi (x = 0, 0.25, 0.5) ribbons prepared by arc-melting and melt-spinning were investigated. The rapidly quenched Co2Ti0.5Fe0.5Si crystallized in the cubic L21 structure whereas Co2Ti0.75Fe0.25Si and Co2TiFe0Si showed various degrees of B2-type disorder. At room temperature, all the samples are ferromagnetic, and the Curie temperature increased from 360 K for Co2TiSi to about 800 K for Co2Ti0.5Fe0.5Si. The measured magnetization also …
Effect Of Disorder On The Magnetic And Electronic Structure Of A Prospective Spin-Gapless Semiconductor Mncrval, P. Kharel, J. Herran, Pavel Lukashev, Y. Jin, J. Waybright, S. Gilbert, B, Staten, P. Gray, S. Valloppilly, Y. Huh, D. J. Sellmyer
Effect Of Disorder On The Magnetic And Electronic Structure Of A Prospective Spin-Gapless Semiconductor Mncrval, P. Kharel, J. Herran, Pavel Lukashev, Y. Jin, J. Waybright, S. Gilbert, B, Staten, P. Gray, S. Valloppilly, Y. Huh, D. J. Sellmyer
Faculty Publications
Recent discovery of a new class of materials, spin-gapless semiconductors (SGS), has attracted considerable attention in the last few years, primarily due to potential applications in the emerging field of spin-based electronics (spintronics). Here, we investigate structural, electronic, and magnetic properties of one potential SGS compound, MnCrVAl, using various experimental and theoretical techniques. Our calculations show that this material exhibits ≈ 0.5 eV band gap for the majority-spin states, while for the minority-spin it is nearly gapless. The calculated magnetic moment for the completely ordered structure is 2.9 µB/f.u., which is different from our experimentally measured value of …
Cycling State That Can Lead To Glassy Dynamics In Intracellular Transport, Monika Scholtz, Stanislav Burov, Kimberly L. Weirich, Björn J. Scholtz, S.M. Ali Tabei, Margaret L. Gardel, Aaron R. Dinner
Cycling State That Can Lead To Glassy Dynamics In Intracellular Transport, Monika Scholtz, Stanislav Burov, Kimberly L. Weirich, Björn J. Scholtz, S.M. Ali Tabei, Margaret L. Gardel, Aaron R. Dinner
Faculty Publications
Power-law dwell times have been observed for molecular motors in living cells, but the origins of these trapped states are not known. We introduce a minimal model of motors moving on a two-dimensional network of filaments, and simulations of its dynamics exhibit statistics comparable to those observed experimentally. Analysis of the model trajectories, as well as experimental particle tracking data, reveals a state in which motors cycle unproductively at junctions of three or more filaments. We formulate a master equation for these junction dynamics and show that the time required to escape from this vortexlike state can account for the …
Observation Of Interlayer Phonon Modes In Van Der Waals Heterostructures, C. H. Lui, Zhipeng Ye, Chao Ji, Kuan-Chang Chiu, Cheng-Tse Chou, Trond I. Andersen, Casie Means-Shively, Heidi Anderson, Jenn-Ming Wu, Tim Kidd, Yi-Hsien Lee, Rui He
Observation Of Interlayer Phonon Modes In Van Der Waals Heterostructures, C. H. Lui, Zhipeng Ye, Chao Ji, Kuan-Chang Chiu, Cheng-Tse Chou, Trond I. Andersen, Casie Means-Shively, Heidi Anderson, Jenn-Ming Wu, Tim Kidd, Yi-Hsien Lee, Rui He
Faculty Publications
We have investigated the vibrational properties of van der Waals heterostructures of monolayer transition metal dichalcogenides (TMDs), specifically MoS2/WSe2 and MoSe2/MoS2 heterobilayers and twisted MoS2 bilayers, by means of ultralow-frequency Raman spectroscopy. We discovered Raman features (at 30–40 cm−1) that arise from the layer-breathing mode (LBM) vibration between the two incommensurate TMD monolayers in these structures. The LBM Raman intensity correlates strongly with the suppression of photoluminescence that arises from interlayer charge transfer. The LBM is generated only in bilayer areas with direct layer-layer contact and an atomically clean interface. Its frequency also …
Manipulation Of Subsurface Carbon Nanoparticles In Bi2sr2cacu2o8+Δ Using A Scanning Tunneling Microscope, A. J. Stollenwerk, N. Hurley, B. Beck, K. Spurgeon, Tim Kidd, G. Gu
Manipulation Of Subsurface Carbon Nanoparticles In Bi2sr2cacu2o8+Δ Using A Scanning Tunneling Microscope, A. J. Stollenwerk, N. Hurley, B. Beck, K. Spurgeon, Tim Kidd, G. Gu
Faculty Publications
We present evidence that subsurface carbon nanoparticles in Bi2Sr2CaCu2O8+δ can be manipulated with nanometer precision using a scanning tunneling microscope. High-resolution images indicate that most of the carbon particles remain subsurface after transport observable as a local increase in height as the particle pushes up on the surface. Tunneling spectra in the vicinity of these protrusions exhibit semiconducting characteristics with a band gap of approximately 1.8 eV, indicating that the incorporation of carbon locally alters the electronic properties near the surface.
Simple, Complete, And Novel Quantitative Model Of Holography For Students Of Science And Science Education, Dale Olson
Simple, Complete, And Novel Quantitative Model Of Holography For Students Of Science And Science Education, Dale Olson
Faculty Publications
A Moiré graphical method for predicting the directions of all permitted image waves for thin and volume holograms is described. This method has been developed in connection with a holography centred optics course for students in science, technology and science education that has evolved over several decades. A somewhat unique view of the holographic process underlies this novel method of predicting the behaviour of diffraction gratings.
Coulomb-Driven Cluster-Glass Behavior In Mn-Intercalated Ti1+Ys2, P. M. Shand, A. L. Meyer, M. Streicher, A. Wilson, T. Rash, Tim Kidd, L. H. Strauss
Coulomb-Driven Cluster-Glass Behavior In Mn-Intercalated Ti1+Ys2, P. M. Shand, A. L. Meyer, M. Streicher, A. Wilson, T. Rash, Tim Kidd, L. H. Strauss
Faculty Publications
We have investigated the low-temperature spin-glasslike phase in the intercalated transition-metal dichalcogenide Mn0.09Ti1.1S2. A departure from Curie–Weiss behavior in the paramagnetic regime indicated the formation of small ferromagnetically correlated clusters. The Vogel–Fulcher law provided an excellent description of relaxation times in the vicinity of the transition, showing that the glasslike phase occurs due to interaction between the clusters. Cole–Cole plots for data close to the transition were linear, which is consistent with a simple exponential distribution of cluster sizes. A Monte Carlo simulation of the dichalcogenide system, including excess self-intercalated Ti ions, gave an …
Quantum Many-Body Calculation Of Mixed-Parity Pairing In The Sr2ruo4 Superconductor Induced By Spin-Orbit Coupling, J. J. Deisz, Tim Kidd
Quantum Many-Body Calculation Of Mixed-Parity Pairing In The Sr2ruo4 Superconductor Induced By Spin-Orbit Coupling, J. J. Deisz, Tim Kidd
Faculty Publications
The unusual superconducting state in Sr2RuO4 has long been viewed as being analogous to a superfluid state in liquid 3He. Nevertheless, calculations based on this odd-parity state are presently unable to completely reconcile the properties of Sr2RuO4. Using a self-consistent quantum many-body scheme that employs realistic parameters, we are able to model several signature properties of the normal and superconducting states of Sr2RuO4. We find that the dominant component of the model superconducting state is of even parity and closely related to superconducting state for the high-Tc …
Reconstructed Fermi Surface Of Underdoped Bi2sr2cacu2o8+Δ Cuprate Superconductors, H.-B. Yang, J. D. Rameau, Z.-H. Pan, G. D. Gu, P. D. Johnson, H. Claus, D. G. Hinks, Tim Kidd
Reconstructed Fermi Surface Of Underdoped Bi2sr2cacu2o8+Δ Cuprate Superconductors, H.-B. Yang, J. D. Rameau, Z.-H. Pan, G. D. Gu, P. D. Johnson, H. Claus, D. G. Hinks, Tim Kidd
Faculty Publications
The Fermi surface topologies of underdoped samples of the high-Tc superconductor Bi2Sr2CaCu2O8+δ have been measured with angle resolved photoemission. By examining thermally excited states above the Fermi level, we show that the observed Fermi surfaces in the pseudogap phase are actually components of fully enclosed hole pockets. The spectral weight of these pockets is vanishingly small at the magnetic zone boundary, creating the illusion of Fermi ‘‘arcs.’’ The area of the pockets as measured in this study is consistent with the doping level, and hence carrier density, of the samples measured. Furthermore, …
Properties Of Hydrogen Terminated Diamond As A Photocathode, J. D. Rameau, J. Smedley, E. M. Muller, T. E. Kidd, P. D. Johnson
Properties Of Hydrogen Terminated Diamond As A Photocathode, J. D. Rameau, J. Smedley, E. M. Muller, T. E. Kidd, P. D. Johnson
Faculty Publications
Electron emission from the negative electron affinity (NEA) surface of hydrogen terminated, boron doped diamond in the [100] orientation is investigated using angle resolved photoemission spectroscopy (ARPES). ARPES measurements using 16 eV synchrotron and 6 eV laser light are compared and found to show a catastrophic failure of the sudden approximation. While the high energy photoemission is found to yield little information regarding the NEA, low energy laser ARPES reveals for the first time that the NEA results from a novel Franck-Condon mechanism coupling electrons in the conduction band to the vacuum. The result opens the door to the development …
Synthesis Of Freestanding Hfo2 Nanostructures, Tim Kidd, Aaron O'Shea, Kayla Boyle, Jeff Wallace, Laura Strauss
Synthesis Of Freestanding Hfo2 Nanostructures, Tim Kidd, Aaron O'Shea, Kayla Boyle, Jeff Wallace, Laura Strauss
Faculty Publications
Two new methods for synthesizing nanostructured HfO2 have been developed. The first method entails exposing HfTe2 powders to air. This simple process resulted in the formation of nanometer scale crystallites of HfO2. The second method involved a two-step heating process by which macroscopic, freestanding nanosheets of HfO2 were formed as a byproduct during the synthesis of HfTe2. These highly two-dimensional sheets had side lengths measuring up to several millimeters and were stable enough to be manipulated with tweezers and other instruments. The thickness of the sheets ranged from a few to a few …
Coercivity And Exchange Bias Of Mn0.25ti1.1s2 In The Cluster-Glass State, P. M. Shand, T. Rash, M. Streicher, T. E. Kidd, K. R. Boyle, Laura Strauss
Coercivity And Exchange Bias Of Mn0.25ti1.1s2 In The Cluster-Glass State, P. M. Shand, T. Rash, M. Streicher, T. E. Kidd, K. R. Boyle, Laura Strauss
Faculty Publications
Magnetic measurements have been carried out on the Mn-intercalated transition-metal dichalcogenide Mn0.25Ti1+yS2. The material, which contained a concentration y≈0.1 of excess intercalated Ti, exhibited paramagnetic behavior at high temperatures with an effective moment per Mn ion of µeff=6.07 ± 0.23 µB, which shows that the system comprises localized Mn2+ moments. A Curie-Weiss temperature ΘCW=-26 ± 1 K indicated that antiferromagnetic interactions were dominant. Deviation from Curie-Weiss behavior below 100 K signaled the formation of antiferromagnetically correlated clusters. Bifurcation of the zero-fieldcooled and field-cooled magnetizations below 20 K …
Doping Of A One-Dimensional Mott Insulator: Photoemission And Optical Studies Of Sr2cu03+Δ, Tim Kidd, T. Valla, P. D. Johnson, K. W. Kim, G. D. Gu, C. C. Homes
Doping Of A One-Dimensional Mott Insulator: Photoemission And Optical Studies Of Sr2cu03+Δ, Tim Kidd, T. Valla, P. D. Johnson, K. W. Kim, G. D. Gu, C. C. Homes
Faculty Publications
Angle-resolved photoemission and optical spectroscopy are used to probe the electronic structure of the one-dimensional Mott insulator Sr2CuO3+δ, both at half-filling and with small concentrations of excess oxygen doping. Spin-charge separation can be seen as evidenced by the existence of spinon and holon branches in the photoemission spectra. Optical studies reveal no significant doping dependence, while photoemission studies show a large energy shift in the spinon and holon states with respect to the main valence band states which remain nearly unaffected. The results suggest the excess dopant carriers are incorporated solely within the one-dimensional Hubbard band …
High-Energy Kink Observed In The Electron Dispersion Of High-Temperature Cuprate Superconductors, T. Valla, T. E. Kidd, W.-G. Yin, G. D. Gu, Z.-H. Pan, A. V. Fedorov
High-Energy Kink Observed In The Electron Dispersion Of High-Temperature Cuprate Superconductors, T. Valla, T. E. Kidd, W.-G. Yin, G. D. Gu, Z.-H. Pan, A. V. Fedorov
Faculty Publications
Photoemission studies show the presence of a high-energy anomaly in the observed band dispersion for two families of cuprate superconductors, Bi2Sr2CaCu2O8+δ and La2-xBaxCuO4. The anomaly, which occurs at a binding energy of approximately 340 meV, is found to be anisotropic and relatively weakly doping dependent. Scattering from short range or nearest neighbor spin excitations is found to supply an adequate description of the observed phenomena.
Fine Details Of The Nodal Electronic Excitations In Bi2sr2cacuso8+Delta, T. Valla, T. E. Kidd, J. D. Rameau, H.-J. Noh, G. D. Gu, P. D. Johnson, H.-B. Yang, H. Ding
Fine Details Of The Nodal Electronic Excitations In Bi2sr2cacuso8+Delta, T. Valla, T. E. Kidd, J. D. Rameau, H.-J. Noh, G. D. Gu, P. D. Johnson, H.-B. Yang, H. Ding
Faculty Publications
Very high energy resolution photoemission experiments on high quality samples of optimally doped Bi2Sr2CaCu2O8+δ show new features in the low-energy electronic excitations. A marked change in the binding energy and temperature dependence of the near-nodal scattering rates is observed near the superconducting transition temperature, TC. The temperature slope of the scattering rate measured at low energy shows a discontinuity at TC. In the superconducting state, coherent excitations are found with the scattering rates showing a cubic dependence on frequency and temperature. The superconducting gap has a d-wave magnitude …
Orbital Dependence Of The Fermi Liquid State In Sr2ruo4, T. E. Kidd, T. Valla, A. V. Fedorov, P. D. Johnson, R. J. Cava, M. K. Haas
Orbital Dependence Of The Fermi Liquid State In Sr2ruo4, T. E. Kidd, T. Valla, A. V. Fedorov, P. D. Johnson, R. J. Cava, M. K. Haas
Faculty Publications
We have used angle-resolved photoemission spectroscopy to determine the bulk electronic structure of Sr2RuO4 above and below the Fermi liquid crossover near 25 K. Our measurements indicate that the properties of the system are highly orbital dependent. The quasi-2D gamma band displays Fermi liquid behavior while the remaining low energy bands show exotic properties consistent with quasi-1D behavior. In the Fermi liquid state below 25 K, the gamma band dominates the electronic properties, while at higher temperatures the quasi-1D ß and α bands become more important.
Quasiparticle Line Shape Of Sr2ruo4 And Its Relation To Anisotropic Transport, S.-C. Wang, H.-B. Yang, A. K. P. Sekharan, H. Ding, J. R. Engelbrecht, X. Dai, Z. Whang, A. Kaminski, T. Valla, T. Kidd, A. V. Fedorov, P. D. Johnson
Quasiparticle Line Shape Of Sr2ruo4 And Its Relation To Anisotropic Transport, S.-C. Wang, H.-B. Yang, A. K. P. Sekharan, H. Ding, J. R. Engelbrecht, X. Dai, Z. Whang, A. Kaminski, T. Valla, T. Kidd, A. V. Fedorov, P. D. Johnson
Faculty Publications
The bulk-representative low-energy spectrum of Sr2RuO4 can be directly measured by angle-resolved photoemission. We find that the quasiparticle spectral line shape of Sr2RuO4 is sensitive to both temperature and momentum. Along the (0, 0)-(π, 0) direction, both gamma and ß bands develop a sharp quasiparticle peak near kF at low temperatures, but as the temperature increases the spectra quickly lose coherent weight and become broad backgrounds above ~130 K, which is the metal-nonmetal crossover temperature, TM, in the c-axis resistivity. However, spectra along the (0, 0)-(π, π) direction evolve smoothly …
Student Explorations Of Quantum Effects In Leds And Luninescent Devices, Lawrence Escalada, N. Sanjay Rebekki, Dean A. Zollman
Student Explorations Of Quantum Effects In Leds And Luninescent Devices, Lawrence Escalada, N. Sanjay Rebekki, Dean A. Zollman
Faculty Publications
We developed activity-based instructional units to introduce basic quantum principles to students with limited physics and mathematics backgrounds. To emphasize the practical applications of contemporary physics, we introduced concepts using the contexts of light-emitting devices such as light-emitting diodes (LEDs), fluorescent lamps, and glow-in-the-dark toys. As our standard of living becomes more dependent on the latest developments in science and technology, our students' literacy must be at a level that enables them to make educated decisions on science- and technology-related issues and their everyday applications. Students need to have at least a basic understanding of 20th-century physics and its applications …
Quantum Melting Of The Charge-Density-Wave State In 1t-Tise2, C. S. Snow, J. F. Karpus, S. L. Cooper, T. E. Kidd, T.-C. Chiang
Quantum Melting Of The Charge-Density-Wave State In 1t-Tise2, C. S. Snow, J. F. Karpus, S. L. Cooper, T. E. Kidd, T.-C. Chiang
Faculty Publications
We report a Raman scattering study of low-temperature, pressure-induced melting of the charge-density- wave (CDW) phase of 1T-TiSe2. Our measurements reveal that the collapse of the CDW state occurs in three stages: (i) For P<5 kbar, the pressure dependence of the CDW amplitude mode energies and intensities are indicative of a ‘‘crystalline’’ CDW regime; (ii) for 5<P<25 kbar, there is a decrease in the CDW amplitude mode energies and intensities with increasing pressure that suggests a regime in which the CDW softens, and exhibits enhanced fluctuations; and (iii) for P > 25 kbar, the absence of amplitude modes reveals a metallic regime in which the CDW has melted.
Electron-Hole Coupling And The Charge Density Wave Transition Intise2, T. E. Kidd, T. Miller, M. Y. Chou, T.-C. Chiang
Electron-Hole Coupling And The Charge Density Wave Transition Intise2, T. E. Kidd, T. Miller, M. Y. Chou, T.-C. Chiang
Faculty Publications
Angle-resolved photoemission is employed to measure the band structure of TiSe2 in order to clarify the nature of the (2 × 2 × 2) charge density wave transition. The results show a very small indirect gap in the normal phase transforming into a larger indirect gap at a different location in the Brillouin zone. Fermi surface topology is irrelevant in this case. Instead, electron-hole coupling together with a novel indirect Jahn-Teller effect drives the transition.
An Investigation On The Impact Of Implementing Visual Quantum Mechanics On Student Learning And Student Instructor Beliefs, Lawrence Escalada
An Investigation On The Impact Of Implementing Visual Quantum Mechanics On Student Learning And Student Instructor Beliefs, Lawrence Escalada
Faculty Publications
Aspects of the Visual Quantum Mechanics instructional materials have been adapted and implemented into a university physical science course for pre-service elementary education majors and various high school physics classrooms. These materials utilize a learning cycle pedagogy involving interactive, simulation computer programs and inexpensive devices to introduce basic quantum physics ideas within the context of fundamental physics concepts. A brief description of how these materials and strategies were adapted and implemented in high school classrooms will be provided. The results found on student conceptual learning and student/instructor attitudes and beliefs will also be briefly discussed.
Sn/Ge(111) Surface Charge-Density-Wave Phase Transition, T. E. Kidd, T. Miller, M. Y. Chou, T.-C. Chiang
Sn/Ge(111) Surface Charge-Density-Wave Phase Transition, T. E. Kidd, T. Miller, M. Y. Chou, T.-C. Chiang
Faculty Publications
Angle-resolved photoemission has been utilized to study the surface electronic structure of 1/3 monolayer of Sn of Ge(111) in both the room-temperature (√3 × √3)R30° phase and the low-temprature (3 × 3) charge-density-wave phase. The results reveal a gap opening around the (3 × 3) Brillouin zone boundary, suggesting a Peierls-like transition despite the well-documented lack of Fermi nesting. A highly sensitive electronic response to doping by intrinsic surface defects is the cause for the unusual behaior, and a detailed calculation illustrates the origin of the (3 × 3) symmetry.
Real And Virtual Images Using A Classroom Hologram, Dale W. Olson
Real And Virtual Images Using A Classroom Hologram, Dale W. Olson
Faculty Publications
No abstract provided.