Showing papers in "Physical Review Letters in 1980"
TL;DR: An exact stochastic simulation of the Schroedinger equation for charged Bosons and Fermions was used to calculate the correlation energies, to locate the transitions to their respective crystal phases at zero temperature within 10%, and to establish the stability at intermediate densities of a ferromagnetic fluid of electrons.
Abstract: An exact stochastic simulation of the Schroedinger equation for charged Bosons and Fermions was used to calculate the correlation energies, to locate the transitions to their respective crystal phases at zero temperature within 10%, and to establish the stability at intermediate densities of a ferromagnetic fluid of electrons.
10,743 citations
TL;DR: In this article, the Hall voltage of a two-dimensional electron gas, realized with a silicon metal-oxide-semiconductor field effect transistor, was measured and it was shown that the Hall resistance at particular, experimentally well-defined surface carrier concentrations has fixed values which depend only on the fine-structure constant and speed of light, and is insensitive to the geometry of the device.
Abstract: Measurements of the Hall voltage of a two-dimensional electron gas, realized with a silicon metal-oxide-semiconductor field-effect transistor, show that the Hall resistance at particular, experimentally well-defined surface carrier concentrations has fixed values which depend only on the fine-structure constant and speed of light, and is insensitive to the geometry of the device. Preliminary data are reported.
5,619 citations
TL;DR: In weak-interaction models with spontaneous parity nonconservation, this article obtained the following formula for the neutrino mass, valid for each lepton generation, which relates the maximality of observed parity non-conservation at low energies to the smallness of neutrinos masses.
Abstract: In weak-interaction models with spontaneous parity nonconservation, based on the gauge group $\mathrm{SU}{(2)}_{L}\ensuremath{\bigotimes}\mathrm{SU}{(2)}_{R}\ensuremath{\bigotimes}\mathrm{U}(1)$, we obtain the following formula for the neutrino mass: ${m}_{{\ensuremath{
u}}_{e}}\ensuremath{\simeq}\frac{{{m}_{e}}^{2}}{g{m}_{{W}_{R}}}$, where ${W}_{R}$ is the gauge boson which mediates right-handed weak interactions. This formula, valid for each lepton generation, relates the maximality of observed parity nonconservation at low energies to the smallness of neutrino masses.
4,895 citations
TL;DR: In this paper, the existence of low-dimensional chaotic dynamical systems describing turbulent fluid flow was determined experimentally by reconstructing phase-space pictures from the observation of a single coordinate of any dissipative dynamical system and determining the dimensionality of the system's attractor.
Abstract: It is shown how the existence of low-dimensional chaotic dynamical systems describing turbulent fluid flow might be determined experimentally. Techniques are outlined for reconstructing phase-space pictures from the observation of a single coordinate of any dissipative dynamical system, and for determining the dimensionality of the system's attractor. These techniques are applied to a well-known simple three-dimensional chaotic dynamical system.
3,628 citations
TL;DR: In this paper, it was shown that different pair potentials lead to different crystal structures, with the use of a Lagrangian which allows for the variation of the shape and size of the periodically repeating molecular-dynamics cell.
Abstract: With use of a Lagrangian which allows for the variation of the shape and size of the periodically repeating molecular-dynamics cell, it is shown that different pair potentials lead to different crystal structures.
2,630 citations
TL;DR: In this paper, the authors reported narrowing and splitting of 7-ps-duration pulses from a mode-locked color-center laser by a 700m-long, singlemode silica-glass fiber, at a wavelength (1.55 \ensuremath{mu}m) of loss and large but negative group-velocity dispersion.
Abstract: This paper reports narrowing and splitting of 7-ps-duration pulses from a mode-locked color-center laser by a 700-m-long, single-mode silica-glass fiber, at a wavelength (1.55 \ensuremath{\mu}m) of loss and large but negative group-velocity dispersion. At certain critical power levels, the observed behavior is characteristic of solitons.
1,844 citations
TL;DR: In this paper, the dipole-dipolecular repulsive interactions organize polystyrene spheres into a two-dimensional triangular lattice and direct microscopic observations of such an interfacial colloidal crystal are reported for the first time.
Abstract: Polystyrene spheres (2450 \AA{} in diameter) are trapped in a surface energy well at water/air interface. Because of asymmetry of charge distribution, electrical dipoles are associated with each interfacial particle. The dipole-dipole repulsive interactions organize the polystyrene spheres into a two-dimensional triangular lattice. The direct microscopic observations of such an interfacial colloidal crystal are reported for the first time.
1,235 citations
TL;DR: In this article, a method for locating the valence-band edge in x-ray photo-emission spectra is reported. But this method is not suitable for measuring semiconductor interface potentials.
Abstract: A highly precise method for locating the valence-band edge in x-ray photoemission spectra is reported. The application to measuring semiconductor interface potentials is discussed. X-ray photoemission-spectroscopy experiments on Ge and GaAs(110) crystals have given Ge $3d$, Ga $3d$, and As $3d$ core level to valence-band edge binding-energy differences of 29.55, 18.81, and 40.73 eV to a precision of \ifmmode\pm\else\textpm\fi{}0.02 eV. For illustration, the valence-band discontinuity at an abrupt Ge/GaAs(110) heterojunction is determined to be 0.53\ifmmode\pm\else\textpm\fi{}0.03 eV.
1,131 citations
TL;DR: In this article, the polymer network of a gel undergoes a discrete transition in equilibrium volume with changes in solvent composition or temperature, and the volume collapse is also observed when the p\mathrm{H}$ within the gel is varied.
Abstract: The polymer network of a gel, under certain conditions, undergoes a discrete transition in equilibrium volume with changes in solvent composition or temperature. This Letter demonstrates that ionization of the gel network plays an essential role in the phase transition. The volume collapse is also observed when the $p\mathrm{H}$ within the gel is varied.
1,101 citations
TL;DR: In this paper, the existence of periodic spontaneous collapse and revival of coherence in the dynamics of a simple quantum model were reported. And the first accurate expressions for the intermediate-time and long-time dynamical behavior of the model were given.
Abstract: This Letter reports on the existence of periodic spontaneous collapse and revival of coherence in the dynamics of a simple quantum model. Also given are the first accurate expressions for the intermediate-time and long-time dynamical behavior of the model.
1,044 citations
TL;DR: In this paper, the interaction effects in disordered Fermi systems are considered in the metallic regime, and logarithmic corrections are obtained for conductivity, density of states, specific heat, and Hall constant.
Abstract: Interaction effects in disordered Fermi systems are considered in the metallic regime. In two dimensions, logarithmic corrections are obtained for conductivity, density of states, specific heat, and Hall constant. These results are compared with a recent theory of localization as well as some experiments.
TL;DR: In this paper, a simple model of disordered systems, called the random energy model, is introduced and solved, where the correlations between the energy levels become negligible and the properties are qualitatively the same as those of the Sherrington-Kirkpatrick model.
Abstract: In this Letter, a simple model of disordered systems---the random-energy model---is introduced and solved. This model is the limit of a family of disordered models, when the correlations between the energy levels become negligible. The properties are qualitatively the same as those of the Sherrington-Kirkpatrick model. Moreover, this random-energy model looks like a simple approximation to any spin-glass model.
TL;DR: In this article, the U(1) generator of the left-right symmetric electroweak model in terms of $B\ensuremath{-}L$ enables us to study the spontaneous breaking of local L$ symmetry.
Abstract: Interpretation of the U(1) generator of the left-right-symmetric electroweak model in terms of $B\ensuremath{-}L$ enables us to study the spontaneous breaking of local $B\ensuremath{-}L$ symmetry. The same Higgs mechanism at the "partial unification" level of $\mathrm{SU}{(2)}_{L}\ensuremath{\bigotimes}\mathrm{SU}{(2)}_{R}\ensuremath{\bigotimes}\mathrm{SU}({4}^{\ensuremath{'}})$ that produces ${\ensuremath{\Delta}}_{L}=2$ processes (e.g., Majorana neutrinos) also yields $\ensuremath{\Delta}B=2$ processes (e.g., "neutron oscillations"). The observation of "neutrinoless" double $\ensuremath{\beta}$ decay and $\ensuremath{\Delta}B=2$ nucleon transitions without proton decay would favor this model and an intermediate mass scale.
TL;DR: In this article, it was shown that the transmitted light from a ring cavity containing a nonlinear dielectric medium undergoes transition from a stationary state to periodic and nonperiodic states, when the intensity of the incident light is increased.
Abstract: It is theoretically shown that the transmitted light from a ring cavity containing a nonlinear dielectric medium undergoes transition from a stationary state to periodic and nonperiodic states, when the intensity of the incident light is increased. The nonperiodic state is characterized by a chaotic variation of the light intensity and associated broadband noise in the power spectrum. The experimental possibility of observing such a transition is also discussed.
TL;DR: In this article, the ternary system potassium laurate-1-decanol-D${2}\mathrm{O}$ was studied over concentration ranges where nematic phases are likely to occur.
Abstract: The phase diagram of the ternary system potassium laurate-1-decanol-D$_{2}\mathrm{O}$ was studied over concentration ranges where nematic phases are likely to occur. Two uniaxial nematic phases which are separated by a biaxial nematic phase are found. In limited concentration range the following phase sequence may be observed reversibly on heating and on cooling: isotropic-uniaxial nematic (positive optical anisotropy)-biaxial nematic-uniaxial nematic (negative optical anisotropy)-biaxial nematic-uniaxial nematic (positive optical anisotropy)-isotropic.
IBM1
TL;DR: In this article, the infrared absorption from molecular monolayers is enhanced by thin metal overlayers or underlayers with use of the attenuated-total-reflection technique, which is consistent with an electric field enhancement due to collective electron resonances associated with the island nature of the thin metal films.
Abstract: The infrared absorption from molecular monolayers is enhanced a factor of 20 by thin metal overlayers or underlayers with use of the attenuated-total-reflection technique. The total enhancement, including contributions from the attenuated-total-reflection geometry, is almost ${10}^{4}$. This effect is consistent with an electric field enhancement due to collective electron resonances associated with the island nature of the thin metal films.
TL;DR: In this article, it was shown that the anisotropy field maintaining the remanent magnetization in the direction of the initial applied field is strongly enhanced by the addition of nonmagnetic Au or Pt impurities.
Abstract: Recent measurements on $\mathrm{Cu}\mathrm{Mn}$ spin-glass alloys have revealed that the anisotropy field maintaining the remanent magnetization in the direction of the initial applied field is strongly enhanced by the addition of nonmagnetic Au or Pt impurities. We show that these results can be accounted for by the existence of Dzyaloshinsky-Moriya-type interactions between the Mn spins arising from spin-orbit scattering of the conduction electrons by nonmagnetic impurities. The magnitude of these interactions is surprisingly large.
TL;DR: The results of a test of general relativity with use of a hydrogen-maser frequency standard in a spacecraft launched nearly vertically upward to 10,000 km are reported in this paper.
Abstract: The results of a test of general relativity with use of a hydrogen-maser frequency standard in a spacecraft launched nearly vertically upward to 10,000 km are reported. The agreement of the observed relativistic frequency shift with prediction is at the 70 x 10 to the -6th level.
TL;DR: In this article, the interferometers now being developed to detect gravitational vaves work by measuring small changes in the positions of free masses, and there has been a controversy whether quantum-mechanical radiation-pressure fluctuations disturb this measurement.
Abstract: The interferometers now being developed to detect gravitational vaves work by measuring small changes in the positions of free masses. There has been a controversy whether quantum-mechanical radiation-pressure fluctuations disturb this measurement. This Letter resolves the controversy: They do.
TL;DR: In this paper, a relation between the spectrum and correlation exponents of the Luttinger model is shown to be a general property of a universality class called Lutteringer liquids.
Abstract: A relation between the spectrum and correlation exponents of the Luttinger model is argued to be a general property of a universality class called "Luttinger liquids." The spinless fermion model equivalent to the $S=\frac{1}{2}$ Heisenberg-Ising -$\mathrm{XY}$ chain in a field is argued to belong to this class, allowing for the first time the systematic calculation of its correlation exponents.
TL;DR: In this article, a new Hamiltonian density formulation of a perfect fluid with or without a magnetic field is presented, where the dynamical variables are the spatial Fourier coefficients of the fluid variables and a Poisson bracket which satisfies the Jacobi identity is defined.
Abstract: A new Hamiltonian density formulation of a perfect fluid with or without a magnetic field is presented. Contrary to previous work the dynamical variables are the physical variables, $\ensuremath{\rho}$, $\stackrel{\ensuremath{\rightarrow}}{\mathrm{v}}$, $\stackrel{\ensuremath{\rightarrow}}{\mathrm{B}}$, and $s$, which form a noncanonical set. A Poisson bracket which satisfies the Jacobi identity is defined. This formulation is transformed to a Hamiltonian system where the dynamical variables are the spatial Fourier coefficients of the fluid variables.
TL;DR: In this paper, a direct infrared absorption method combining a liquid-nitrogen-cooled multiple-reflection discharge cell and a difference-frequency laser system has been used for the detection of this fundamental molecular ion in any spectral range.
Abstract: The infrared ${\ensuremath{
u}}_{2}$ band of ${\mathrm{H}}_{3}^{+}$ has been observed. A direct infrared absorption method combining a liquid-nitrogen-cooled multiple-reflection discharge cell and a difference-frequency laser system has been used for the detection. Fifteen absorption lines have been measured in the region of 2950-2450 ${\mathrm{cm}}^{\ensuremath{-}1}$ and assigned. This is the first spectroscopic detection of this fundamental molecular ion in any spectral range.
TL;DR: In this paper, it was shown that such an asymmetric state is a general consequence of the evolution of developed magnetohydrodynamic turbulence, which tends, as a consequence of nonlinear interactions, towards a state where the only modes left are those initially prevailing (with either cross helicity + 1 or - 1).
Abstract: The solar-wind magnetohydrodynamic turbulence is observed to be mainly made of Alfv\'enic fluctuations propagating away from the sun. It is shown that such an asymmetric state is a general consequence of the evolution of developed magnetohydrodynamic turbulence, which, starting from an initial asymmetry between modes with cross helicity + 1 and - 1, tends, as a consequence of nonlinear interactions, towards a state where the only modes left are those initially prevailing (with either cross helicity + 1 or - 1).
TL;DR: A massive Dirac neutrino has a magnetic moment which causes its spin to precess in a magnetic field This reduces the effective weak cross sections for relativistic neutrinos as discussed by the authors.
Abstract: A massive Dirac neutrino has a magnetic moment, which causes its spin to precess in a magnetic field This reduces the effective weak cross sections for relativistic neutrinos An estimate on the basis of phenomenological considerations as well as the standard electroweak theory indicates that massive neutrinos from supernovae and neutron stars may contain significant mixtures of negative- and positive-helicity states
TL;DR: In this paper, it was shown that an infinite sequence of spatially modulated commensurate phases, with wave vectors, occurs in simple, anisotropic Ising models with nn couplings, in between spin-textonehalf layers, and competing nnn interlayer couplings along one axis.
Abstract: On the basis of systematic low-temperature expansions "to all orders", it is shown that an infinite sequence of spatially modulated commensurate phases, with wave vectors $\frac{\ensuremath{\pi}j}{(2j+1)a}$ ($j=0, 1, 2, \dots{}$), occurs in simple, anisotropic Ising models with nn couplings ${J}_{0}$, ${J}_{1}g0$, in between spin-\textonehalf{} layers, and competing nnn interlayer couplings ${J}_{2}=\ensuremath{-}k{J}_{1}$ along one axis. The free energies, interfacial tensions, and phase boundaries are found for low $T$ in $dg2$ dimensions.
TL;DR: For neutrinos of mass $30{m}_{30}$ eV, a maximum Jeans mass was derived in this article, where neutrino fluctuations were damped, and the growth of baryon fluctuations was greatly inhibited.
Abstract: If neutrinos dominate the mass density of the Universe, they play a critical role in the gravitational instability theory of galaxy formation. For neutrinos of mass $30{m}_{30}$ eV, a maximum Jeans mass ${M}_{\ensuremath{
u}m}\ensuremath{\approx}4\ifmmode\times\else\texttimes\fi{}{10}^{15}{{m}_{30}}^{\ensuremath{-}2}{M}_{\ensuremath{\bigodot}}$ is derived. On smaller scales, neutrino fluctuations are damped, and the growth of baryon fluctuations is greatly inhibited. Structures on scales $g{M}_{\ensuremath{
u}m}$ may collapse, forming galaxies as in Zel'dovich's "pancake" theory.
TL;DR: In this paper, a new class of layered materials has been prepared by alternate deposition of two dissimilar metals, and strong experimental evidence is shown that coherent structures with layer thicknesses approaching interatomic spacing can be prepared in this fashion.
Abstract: A new class of layered materials has been prepared by alternate deposition of two dissimilar metals. Strong experimental evidence is shown that coherent structures with layer thicknesses approaching interatomic spacing can be prepared in this fashion. The experimental x-ray measurements are found to be in good qualitative and quantitative agreement with model calculations.
TL;DR: In this paper, a generalization of the nonlinear model is considered, where the field takes values in a compact manifold M and the coupling is determined by a Riemannian metric on H. The model is renormalizable in 2 + ~ dimensions, the renormalization group acting on the infinite dimensional space of RiemANNian metrics.
Abstract: A generalization of the nonlinear ~ model is considered. The field takes values in a compact manifold M and the coupling is determined by a Riemannian metric on H. The model is renormalizable in 2 + ~ dimensions, the renormalization group acting on the infinite dimensional space of Riemannian metrics. Topological properties of the p-function and solutions of the fixed point equation R{sub ij}-αg{sub ij}=∇{sub i}v{sub j}+∇{sub j}v{sub i}, α=±1 or 0, are discussed.
TL;DR: In this article, it was shown that even waves which carry little toriodal momentum, such as electron cyclotron waves, may be attractive as a means for generating steady-state toroidal current in a tokamak.
Abstract: Preferential heating of electrons traveling in one direction can support a current even in the absence of a dc electric field. An immediate implication is that even waves which carry little toriodal momentum, such as electron cyclotron waves, may be attractive as a means for generating steady-state toroidal current in a tokamak. An analytical expression is derived for the current generated per power dissipated, which agrees remarkably well with numerical calculations.