UScholar Works
 
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CreatorTitleDescriptionSubjectDate
26 Mattis, Daniel C.Magnetization of Ising model in nonzero magnetic fieldKnowing only the zero-field magnetization (e.g., Yang's result) of the Ising model in any number of dimensions, one can construct a lower bound on m(h), the magnetization in finite field. Knowledge of u, the internal energy per bond, enables a more efficient lower bound to be constructed. Both are ...Magnetization; Griffiths inequality1969
27 Ailion, David CharlesLow cost integrated circuit versatile pulse and frequency counterIn this paper we describe a compact multipurpose counter whose design is based on the use of plastic integrated circuits. The circuit contains about $90 worth of semiconductor components and is very easy to wire; nevertheless, it is extremely versatile. It consists of dual 107 and 106 counters which...Integrated circuits; Counters; Physics instruments1969
28 Ailion, David CharlesNew two-point calibration method for platinum resistance thermometers for the range 75-400KIn this paper we describe a new method for calibrating high quality platinum resistance thermometers to ±0.01 "C over the temperature range 75-400 K. This method requires resistance measurements at only two temperatures (liquid nitrogen and the ice point) in contrast to other methods which require ...Platinum; Resistance thermometers; Physics instruments1969
29 Ailion, David CharlesLow cost high linearity solid state digital double boxcarIn this article, we describe a digital solid state double boxcar of infinite holding time and very high linearity. It uses a Hewlett-Packard (HP2212 A-M3) voltage-to-frequency converter (VFC) whose output is accumulated on a running counter, thereby providing signal averaging with an infinite holdin...High linearity; Boxcar; Instruments, Physics1969
30 Mattis, Daniel C.Effects of orbital degeneracy on a magnetic impurity in a nonmagnetic metalWe study the Green's-function equations for a version of the two-orbital Anderson model of a magnetic impurity, in an approximation scheme that displays the logarithmic anomalies and enables the Kondo temperature Tĸ to be calculated as a function of the parameters. The nature of the solutions is ex...Orbital degeneracy; Magnetic impurities; Nonmagnetic metal; Kondo temperature; Anomalous resonances1969-02
31 Symko, Orest GeorgeAdiabatic compressional cooling of He3By adiabatic compression of a two-phase mixture of liquid and solid He3, temperatures below 2.5 mK have been obtained. These are in the range expected for nuclear ordering in solid He3.He3; Adiabatic compressional cooling1969-03
32 Mattis, Daniel C.Theory of electronic switching effect as a cooperative phenomenonA modified form of Zener tunneling theory, in which we assume that the tunneling barrier is a decreasing collective function of electronic excitation, is shown to imply insulator- to-metal switching characteristics similar to those reported by Ovshinsky for glass film devices. In addition, our І-V ...Electronic switching; Negative resistance1969-05
33 Symko, Orest GeorgeSubstantial nuclear ordering in solid He3Evidence for a substantial nuclear ordering in solid bcc He3 at melting pressure has been inferred from solid entropies s s deduced from measurements of the slope of the melting curve for a liquid-solid mixture cooled by adiabatic compression. At 3.4 mK we find experimentally that sS/R = 0.83 ln2. I...Solid He3; Nuclear ordering; Ordered nuclear spins; Bulk nuclear polarization1969-11
34 Mattis, Daniel C.Existence of two phase transitions in Hubbard modelWe solve the Hubbard model, for one electron per atom in a simple cubic structure, using one-particle Green's functions. We determine the accuracy of this calculation to be good by comparison with an exact solution by Lieb and Wu of a one-dimensional limiting case.Critical temperature1969-12
35 Mattis, Daniel C.Switching in magnetite: a thermally driven magnetic phase transitionWe have performed a variety of experiments on switching phenomena in a metal oxide, magnetite. Our findings are consistent with Joule microheating which drives the Verwey transition occurring at 119 K. We conclude that considerations of band structure, direct electric-field-induced transitions, tunn...Negative resistance; Electrical switching; Verwey transition; Joule heating1969-12
36 DeTar, CarletonMultiperipheral dynamics at general momentum transferWe extend the group-theoretical analysis of the multiperipheral integral equation of Chew, Goldberger, and Low to general momentum transfers. Using a set of variables for the multiparticle phase space analogous to those of Bali, Chew, and Pignotti, we obtain, through the 0(2,1) symmetry, a partial...Multiperipheral model1969-12
37 Ailion, David CharlesFrequency modulation method for performing adiabatic demagnetization in the rotating reference frameA new method for preforming adiabatic demagnetization in the rotating reference frame in NMR experiments is presented in this paper. In this new method the frequency of a crystal oscillator rather than the actual magnetic field is pulsed off resonance. Using simple circuits which are described in th...Demagnetization; Physics experiments; NMR1970
38 Ailion, David CharlesSelf-switching Q-damping circuit for reducing transmitter ringdown time in high power pulse NMRIn this paper we describe a circuit for reducing the transmitter ringdown time and thereby improving the recovery time in pulse NMR experiments. The circuit uses only solid state devices and requires no external switching. For transmitter voltages less than 0.5 V peak to peak the effective resista...Circuits; NMR experiments; Rf pulse1970
39 DeTar, CarletonO(2,1) decomposition of the equal-mass multipheripheral equation at t=0We extend the results of a group-theoretical analysis of the t=0 multiperipheral equation to the case t<0 for pairwise equal masses. Using variables discussed in a previous paper, we diagonalize the equation in the Bali-Chew-Pignotti (BCP) model with respect to the 0(2, 1) group and relate the solut...Multiperipheral model; Unitaries1970-05
40 Mattis, Daniel C.Role of phonons and band structure in metal-insulator phase transitionWe present a soluble model of electrons interacting with lattice vibrations which displays metallic, superconducting, and insulating phases. We solve the thermodynamics of this model and discuss its properties. The metal-insulator phase transition is second order for sc and bcc tight-binding bands. ...Band structure1970-08
41 DeTar, CarletonTwo-fireball phenomenon and the multiperipheral modelIn the context of the Chew-Snider version of the Amati-Bertocchi-Fubini-Stanghellini-Tonin pion-exchange model, we investigate certain multiperipheral mechanisms that could account for those phenomena that have hitherto motivated the two-fireball model. These mechanisms are (1) double diffractive ...Multiperipheral model; Fireballs1970-08
42 Mattis, Daniel C.Two-dimensional Ising model in a finite magnetic fieldWe present the results of numerical calculations giving accurate estimates of the magnetization of the two-dimensional Ising model on a square lattice. Moreover, we argue that these results are strict lower bounds to the correct magnetization M(H, T). The estimates are obtained by dividing the infin...Magnetization1970-10
43 Symko, Orest GeorgeContinuously operating 4He evaporation refrigeratorA simple and compact device was developed to provide continuous, self-regulating refrigeration at approximately 1.3 K. The temperature of the device remains nearly constant, independent of external power, up to a critical power. For a molar flow rate of 10^-4 moles/sec, the refrigerator can absorb...4He evaporation refrigerator1971
44 DeTar, CarletonMomentum spectrum of hadronic secondaries in the multiperipheral modelMotivated by a simplified multiperipheral model, we formulate a general qualitative description of the momentum spectrum of secondaries, resulting from a collision of two hadrons at high energies. Arguing from two fundamental multiperipheral concepts, (a) that transverse momenta are limited and (b...Secondaries; Multiperipheral model; Fireballs1971-01
45 Mattis, Daniel C.Critical curves and thermodynamic phases of lattice fluids and antiferromagnets with structured interactionsWe study the classical lattice gas with hard cores, nearest-neighbor repulsive forces, and next-nearest-neighbor attractive forces. We find several thermodynamic phases (vapor, liquid, and solid) and unusually shaped critical curves, yet no critical point or triple point. We find and discuss discont...Ising antiferromagnet; Molecular field theory1971-06
46 Mattis, Daniel C.Short-range versus long-range order in a model binary alloyWe calculate the free energy of a linear binary metallic alloy using an exact transfer-matrix formalism. We obtain for the first time the electronic band structure when there is nonvanishing short-range order and calculate the temperature dependence of the short-range order parameter. Following Foo...Binary alloys; Density of state; Free energy1971-07
47 Mattis, Daniel C.Exactly solvable model of a magnetic impurityA slight modification of the "mixing" term in Anderson's model of a magnetic impurity produces an exactly solvable model. Results of some preliminary calculations are given, and upper and lower bounds on Anderson's model are obtained by means of the exact solutions. .Magnetic impurity; Ground-state energy; Free energy1971-11
48 Ailion, David CharlesNew technique for determining the diffusion mechanism by NMR: application to Cl35 diffusion in TlClA major problem in the study of atomic motions is the determination of the dominant mechanism responsible for translational diffusion. Recently Ailion and Ho predicted that the rotating-frame spin-lattice relaxation time T l p would have an angular dependence which depends on the diffusion mechanis...Diffusion; Solids; NMR1972
49 Mattis, Daniel C.Exactly soluble model of interacting electronsWe diagonalize a many-fermion Hamiltonian consisting of terms quadratic as well as quartic in the field operators. A dual spectrum of eigenstates is an interesting result. We also derive a formula for obtaining the free energy at finite temperature.Eigenstates; Free energy; Excitation spectrum1972
50 Ailion, David CharlesProtein hydration changes in the formation of the nicotinamide adenine dinucleotide complexes of glyceraldehyde 3-phosphate dehydrogenase of yeast. II. The spin lattice relaxation of solvent water protonsThe glyceraldehyde 3-phosphate dehydrogenase of yeast is known to undergo a particle volume contraction and the commensurate loss of a hydration component when it forms a complex with NAD. We have inquired whether the water movement in the conformational transition can be monitored by measurements ...Protein hydration; Nicotinamide adenine dinucleotide complexes; Glyceraldehyde 3 phosphate dehydrogenase; Solvent water protons1973
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