We report the electrical transport properties of graphene for dilute alkali metal decoration (n ∼ 2 × 1012 cm−2) at cryogenic temperatures. Upon deposition of K and Li atoms at T = 20 K, graphene devices are doped with electrons, and the charge carrier mobility is decreased. As temperature is increased, the number of electrons donated to the graphene and the number of charged scatterers are reduced, and the mobility of the metal decorated graphene is increased. This differs from the typical temperature-dependent transport in undecorated graphene, where the mobility decreases with increasing temperature. To investigate the kinetic behavior of adatoms on graphene, we estimate the hopping time of the Li and K adatoms on graphene based on the migration barrier in the low concentration regime of the metal adatoms by Density Functional Theory calculations. The calculations reveal that these adatoms are mobile even at cryogenic temperatures and become more mobile with increasing temperature, allowing for cluster formation of adatoms. This indicates that the dominant factor in the electron transport on warming is a cluster formation.

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Reported is an experimental and computational investigation of the low temperature heat capacity, thermodynamic functions, and thermal conductivity of stoichiometric, polycrystalline CeO 2. The experimentally measured heat capacity at T < 15 K provides an important correction to the historically accepted experimental values, and the low temperature thermal conductivity serves as the most comprehensive data set at T < 400 K available. Below 10 K, the heat capacity is observed to obey the Debye T 3 law, with a Debye temperature of ΘD = 455 K. The entropy, enthalpy, and Gibbs free energy functions are obtained from the experimental heat capacity and compared with predictions from Hubbard-corrected density functional perturbation theory calculations using the Perdew, Burke, and Ernzerhof parameterization revised for solids. The thermal conductivity is determined using the Maldonado continuous measurement technique, along with laser flash analysis, and analyzed according to the Klemens-Callaway model.

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We report the properties of superconductivity and Hall effect in 100 nm Pb[Formula: see text]Bi[Formula: see text] alloy thin films which were prepared by thermal evaporation with quench condensation using liquid nitrogen. X-ray diffraction indicates the films are [Formula: see text]-phase with peaks shifted to lower angles compared to pure Pb. The [Formula: see text] of the films was higher than those of an amorphous Pb–Bi alloy thin film of the same composition and pure bulk Pb. The resistivity, critical field and critical current density of the thin films are reported. The coherence length ([Formula: see text][Formula: see text]) and London penetration depth ([Formula: see text]) near [Formula: see text] were calculated from the experimental results. The films are in the dirty limit and behave as type-II superconductors with a Ginzburg–Landau parameter of about 10. Additionally, the films show sign reversal in Hall measurements. These films have been quite useful in a comprehensive study of the effects of flux pinning by integrated ferromagnetic nanostructures conducted in hybrid ferromagnet–superconductor samples in our lab over the past few years due to their single-phase nature and strong type-II behavior.