English
Related papers

Related papers: Magnetic Superstructure and Metal-Insulator Transi…

200 papers

We investigate Mn substitution at the Fe site in PrFe1-xMnxAsO0.7F0.3 (0 to 0.1) using structural, Raman, density functional theory (DFT), transport, and magnetic measurements. X-ray diffraction and Raman analyses confirm preferential Mn…

A temperature-dependent EXAFS investigation of La{1-x}Ca{x}MnO3 is presented for the concentration range that spans the ferromagnetic-insulator (FMI) to ferromagnetic-metal (FMM) transition region, x = 0.16-0.22. The samples are insulating…

Strongly Correlated Electrons · Physics 2009-11-13 Y. Jiang , F. Bridges , L. Downward , J. J. Neumeier

In this work we report electron spin resonance (ESR) measurements in the semiconducting Ce1-xGdxFe4P12 (x ~ 0.001) filled skutterudite compounds. Investigation of the temperature (T) dependence of the ESR spectra and relaxation process…

Strongly Correlated Electrons · Physics 2015-10-28 F. A. Garcia , J. G. S. Duque , P. G. Pagliuso , C. Rettori , Z. Fisk , S. B. Oseroff

We report on the first experimental observation of an apparent metal insulator transition in a 2D electron gas confined in an InAs quantum well. At high densities we find that the carrier mobility is limited by background charged impurities…

Mesoscale and Nanoscale Physics · Physics 2014-10-15 J. Shabani , S. Das Sarma , C. J. Palmstrøm

The magnetic field-induced superconductor-insulator-metal transition (SIMT) in partially deuterated $\kappa$-(BEDT-TTF)$_2$Cu[N(CN)$_2$]Br, which is just on the Mott boundary, has been observed using the infrared magneto-optical imaging…

A resonant inelastic x-ray scattering study of the electronic structure of the semiconductor cuprous oxide, $\rm Cu_2O$, is reported. When the incident x-ray energy is tuned to the Cu K-absorption edge, large enhancements of the spectral…

Materials Science · Physics 2012-06-18 Young-June Kim , J. P. Hill , H. Yamaguchi , T. Gog , D. Casa

The electronic properties of SrRuO3/LaAlO3 (SRO/LAO) superlattices with different interlayer thicknesses of SRO layers were studied. As the thickness of SRO layers is reduced, the superlattices exhibit a metal-insulator transition implying…

The phase diagram of Ca$_{2-x}$Sr$_x$RuO$_4$ has been studied by neutron diffraction on powder and single-crystalline samples. The experiments reveal antiferromagnetic order and structural distortions characterized by tilts and rotations of…

Superconductivity · Physics 2009-10-31 O. Friedt , M. Braden , G. Andre , P. Adelmann , S. Nakatsuji , Y. Maeno

Detailed measurements of the magnetic and transport properties of the two La1-xCaxMnO3 (x = 0.18, x = 0.20) single crystals straddling the compositional metal-insulator transition boundary (0.18 < xc < 0.22) are summarized. The analysis of…

Strongly Correlated Electrons · Physics 2009-01-15 Wanjun Jiang , X. Z. Zhou , K. Glazyrin , Y. Mukovskii , Gwyn Williams

Anomalous metal-insulator transition observed in filled skutterudite CeOs$_4$Sb$_{12}$ is investigated by constructing the effective tight-binding model with the Coulomb repulsion between f electrons. By using the mean field approximation,…

Strongly Correlated Electrons · Physics 2009-11-11 Yoshiki Imai , Keitaro Sakurazawa , Tetsuro Saso

The apparent metal-insulator transition is observed in a high quality two-dimensional electron system (2DES) in the strained Si quantum well of a Si/Si_{1-x}Ge_x heterostructure with mobility \mu=1.9 x 10^5 cm^2/Vs at density n=1.45 x…

Mesoscale and Nanoscale Physics · Physics 2007-05-23 K. Lai , W. Pan , D. C. Tsui , S. A. Lyon , M. Muhlberger , F. Schaffler

The electronic structure of CuIr$_2$S$_4$ has been investigated using various bulk-sensitive x-ray spectroscopic methods near the Ir $L_3$-edge: resonant inelastic x-ray scattering (RIXS), x-ray absorption spectroscopy in the partial…

Strongly Correlated Electrons · Physics 2012-06-18 H. Gretarsson , Jungho Kim , D. Casa , T. Gog , K. R. Choi , S. W. Cheong , Young-June Kim

Molecular orbital (MO) systems with clusters of heavy transition metal (TM) ions are one of the most important classes of model materials for studying the interplay between local physics and effects of itinerancy. Despite a large number of…

Resonant inelastic X-ray scattering (RIXS) at the $L$-edge of transition metal elements is now commonly used to probe single magnon excitations. Here we show that single magnon excitations can also be measured with RIXS at the $K$-edge of…

Temperature, magnetic induction and substitution dependent resistivity are a crucial factor in determining the physical properties of magneto-resistive materials. The first objective of this work was to find out an applicable method of…

General Physics · Physics 2017-01-18 Changshi Liu

The ultrafast response of the prototype Mott-Hubbard system (V1-xCrx)2O3 was systematically studied with fs pump-probe reflectivity, allowing us to clearly identify the effects of the metal-insulator transition on the transient response.…

Strongly Correlated Electrons · Physics 2011-08-29 B. Mansart , D. Boschetto , S. Sauvage , A. Rousse , M. Marsi

Recent improvements in instrumentation have established resonant inelastic x-ray scattering (RIXS) as a valuable new probe of the magnetic excitations in the cuprates. This article introduces RIXS, focusing on the Cu $L_3$ resonance, and…

Superconductivity · Physics 2015-02-17 M. P. M. Dean

The low-temperature resistivity of a SiGe 2-dimensional hole gas has been studied using the gate controlled carrier density as a parameter. A metal-insulator transition is seen both in the temperature and in the electric field behaviour.…

Mesoscale and Nanoscale Physics · Physics 2007-05-23 V. Senz , U. Doetsch , U. Gennser , T. Ihn , T. Heinzel , K. Ensslin , R. Hartmann , D. Gruetzmacher

We report results of NMR experiments on the ruthenium oxide Hg2Ru2O7 with the pyrochlore structure, which exhibits a metal-insulator transition at TMI = 107 K. In the metallic phase above TMI, the nuclear spin-lattice relaxation rate 1/T1…

Strongly Correlated Electrons · Physics 2017-12-01 Makoto Yoshida , Masashi Takigawa , Ayako Yamamoto , Hidenori Takagi

We report a study of spin waves in hole-doped ferromagnetic La7/8Sr1/8MnO3, in the metallic state (165K) below TC (181K) and through the puzzling metal-insulator transition which occurs at TO'O''=159K. They reveal very unusual excitations.…

Strongly Correlated Electrons · Physics 2007-05-23 M. Hennion , F. Moussa , P. Lehouelleur , P. Reutler , A. Revcolevschi