Christian Platt

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The development of a sensitive filter radiometer for the Atmospheric Radiation Measurement (ARM) Program has been reported by Platt et al. (1994, 1995). The aim was to develop a reliable and fast instrument that could be used alongside a lidar to obtain near realtime optical properties of clouds, particularly high ice clouds, as they drifted over an ARM(More)
The Maritime Continent Thunderstorm Experiment (MCTEX) provided another opportunity to study tropical cirrus and anvil clouds. The component of the experiment that included the lidar and radars was supported by the ARM Program. The experiment has provided a further set of data to categorize tropical cirrus in terms of their cloud-radiation interactions, a(More)
A narrow beam fast filter radiometer has been developed for the Atmospheric Radiation Measurement (ARM) Program. The radiometer is intended to operate alongside a lidar at ARM sites in a lidar/radiometer (LIRAD) configuration. The radiometer detects in three narrow bands at 8.62-, 10.86-, and 12.04-m central wavelengths in the atmospheric window. In(More)
We put forward a scenario that explains the difference between the order-parameter character in arsenide (As) and phosphorous (P) iron-based superconductors. Using functional renormalization group to analyze it in detail, we find that nodal superconductivity on the electron pockets (hole pocket gaps are always nodeless) can naturally appear when the hole(More)
We investigate the superconducting phase in the K(x)Ba(1-x)Fe2As2 122 compounds from moderate to strong hole-doping regimes. Using the functional renormalization group, we show that, while the system develops a nodeless anisotropic s(±) order parameter in the moderately doped regime, gapping out the electron pockets at strong hole doping drives the system(More)
Since its discovery, the superconducting phase in water-intercalated sodium cobaltates Na(x)CoO2·yH2O (x∼0.3, y∼1.3) has posed fundamental challenges in terms of experimental investigation and theoretical understanding. By a combined cluster calculation and renormalization group approach, we find an anisotropic chiral d+id-wave state as a consequence of(More)
In this section we elaborate on various technical details of the pseudofermion functional renormalization group method, which we apply to map out the phase diagram of the KHM. As mentioned in the paper, we first express the spin operators in terms of pseudofermions, using the representation S = 1/2 ∑ αβ f † ασ μ αβfβ , (α, β =↑, ↓, μ = x, y, z) with(More)
We investigate the competing Fermi surface instabilities in the kagome tight-binding model. Specifically, we consider on-site and short-range Hubbard interactions in the vicinity of van Hove filling of the dispersive kagome bands where the fermiology promotes the joint effect of enlarged density of states and nesting. The sublattice interference mechanism(More)
The search for topological superconductors has recently become a key issue in condensed matter physics, because of their possible relevance to provide a platform for Majorana bound states, non-Abelian statistics, and quantum computing. Here we propose a new scheme which links as directly as possible the experimental search to a material-based microscopic(More)
The retrieval of cloud properties from Lidar/Radiometer data by the LIRAD method is described. Several data sets taken by the CSIRO Division of Atmospheric Research are now available for such retrievals as a result of several major field experiments during the past six years. The LIRAD method is reviewed briefly and its application to the various data sets(More)