M. S. da Luz

Procedure for measuring electrical resistivity of anisotropic materials: A revision of the Montgomery method

A procedure for determining the electrical resistivity of anisotropic materials is presented. It offers several improvements to the well-known Montgomery method. One improvement, in particular, is the ability to obtain the electrical resistivity for all three axes of an orthorhombic crystal analytically, rather than using the iterative approach suggested by Montgomery for the third axis. All necessary equations are derived and their application in determining the tensor components of the electrical resistivity is explained in detail. Measurements on isotropic specimens were executed in order to test the foundations of the method. Measurements on anisotropic samples are compared with measurements obtained by using the standard four-probe method, revealing good agreement.

Interplay between antiferrodistortive, ferroelectric, and superconducting instabilities in Sr1-x Ca-x TiO3-delta

SrTiO

Ta1-xHfxB: A new FeB-prototype superconductor

_{3}

Synthesis of HgPb2 assisted by high energy ball milling

undergoes a cubic-to-tetragonal phase transition at 105K. This antiferrodistortive transition is believed to be in competition with incipient ferroelectricity. Substituting strontium by isovalent calcium induces a ferroelectric order. Introducing mobile electrons to the system by chemical non-isovalent doping, on the other hand, leads to the emergence of a dilute metal with a superconducting ground state. The link between superconductivity and the other two instabilities is an open question, which gathers momentum in the context of the growing popularity of the paradigm linking unconventional superconductors and quantum critical points. We present a set of specific-heat, neutron-scattering and dielectric permittivity and polarization measurements on Sr

Current-tuned superconductor to insulator transition in granular Sm1.82Ce0.18CuO4-delta superconductor

_{1-x}

Diamagnetism and structural transition in the Ba2Cu3O4Cl2 compound

Ca

Single crystal growth and characterization of MnAs

_{x}

Electrical resistivity, high-resolution thermal expansion, and heat capacity measurements of the charge-density wave compound γ-Mo4O11

TiO

Electrical transport in single-crystalline Li 0.9 Mo 6 O 17 : A two-band Luttinger liquid exhibiting Bose metal behavior

_{3}

High-resolution measurements of the thermal expansion of superconducting Co-doped BaFe2As2

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