Spin-Glass-Like Behavior in Very Dilute PdFe at Very Low Temperatures

Measurements of the electrical resistivity of palladium, residual resistivity ratio ∼22 500, containing 1.7 ppm of Fe have been made from 5.5 K to 1.8 mK. 15 Hz ac susceptibility measurements from 1 K to 1.8 mK together with the resistivity data suggest that a transition into a spin-glass state occurs near 7 mK

Relationship between the Linear Ringing Frequencies in 3He-A and 3He-B near the Polycritical Point

New measurements of parallel ringing in a quasi-ideal geometry for 3He-B near the temperature and pressure of the polycritical point suggest fB2/fA2∼5/2, where fB and fA are the linear parallel-ringing frequencies at a given temperature near Tc. This result approaches the prediction of theory using the Anderson-Brinkman-Morel and Balian-Werthamer states to describe 3He-A and 3He-B, respectively, and hence the results of Osheroff at melting pressure, but disagrees with earlier observations at pressures near the polycritical point

Relaxation of the Wall-Pinned Magnetization Ringing Mode in Superfluid 3He-B

Observations of the wall-pinned mode in 3He-B allow new magnetic relaxation phenomena to be studied. Excepting the quantitative value of the zero-time ringing frequency, comparison of experiment with theory is satisfactory, including a linear dependence of the square of the ringing period on time and a square-root singularity near Tc in the relaxation parameter

Experiments on Dynamic Parallel Magnetism in Superfluid 3He

Observations are reported of the ringing of parallel magnetization in superfluid 3He when an incremental magnetic field parallel to a steady field is suddenly turned off

Nonlinear Parallel Ringing of Magnetization in Superfluid 3He

Experiments based on an analogy to the ac Josephson effect have shown in both 3He-A and 3He-B that a pairing theory of the superfluidity of 3He is essentially correct. Additional observations of parallel ringing are not in agreement with the simple pendulum models used to describe nonlinear dynamic magnetic effects

Origin of the Peaked Structure in the Conductance of One-Dimensional Silicon Accumulation Layers

We have made extensive studies of the temperature, gate voltage, and electric field dependences of the conductance peaks in small silicon inversion layers in order to distinguish between resonant-tunneling models and a hopping model. We find that many of the peaks are consistent only with a hopping model, whereas some could be consistent with an early resonant-tunneling model. None of our structure is consistent with resonant tunneling if the recent formulation of Stone and Lee is correct

Bringing Agriculture into the GATT: Designing Acceptable Agricultural Policies

Agricultural and Food Policy, International Relations/Trade,

Observation of Resonant Tunneling in Silicon Inversion Layers

Measurements of the temperature and carrier-density dependence of the strongly localized conductance of short silicon inversion layers are reported. At the lowest temperatures we observe well-isolated, large conductance peaks whose width and temperature dependence are only consistent with resonant tunneling and are inconsistent with Mott hopping. Several new features are observed which we believe may be the result of Coulomb interactions

HDE 233517: Lithium and Excess Infrared Emission in Giant Stars

Recent studies have identified a small class of moderately rapidly rotating, chromospherically active, single giants, some of which are lithium rich. We present evidence suggesting the peculiar K-type star HDE 233517 is one such object. Previously, HDE 233517 has been suggested to be a young star, consistent with its large far-infrared excess and our log ε(Li) ~ 3.3. However, our high-resolution spectroscopic observations show it is likely a single, post-main-sequence K2 giant with v sin i = 15 km s-1 and modest Ca II H and K emission. The giant status of HDE 233517 is determined directly from luminosity-sensitive line ratios and a lack of significant line wings, and is further supported by a large radial velocity (46.5 km s-1), small proper motion, and the presence of interstellar absorption features. Interpretation of the data in the context of a recent mass outflow model for giant stars proposed by de la Reza and coworkers indicates that HDE 233517 has the largest mass-loss rate, ~3 × 10-7 M☉ yr-1, of any known luminosity class III giant. We suggest that the processes causing rapid rotation, large lithium abundance, and infrared excess are triggered at the base of the giant branch when the convection zone reaches the rapidly rotating core of low-mass stars