A5102762116- Magnetic and transport properties of perovskites and related materials
- Magnetism in coordination complexes
- Organic and Molecular Conductors Research
- Ga2O3 and related materials
- Electronic and Structural Properties of Oxides
- Electron and X-Ray Spectroscopy Techniques
- Transition Metal Oxide Nanomaterials
- Physics of Superconductivity and Magnetism
- Multiferroics and related materials
- Catalytic Processes in Materials Science
- Advanced Thermoelectric Materials and Devices
- MXene and MAX Phase Materials
- Thermal properties of materials
- 2D Materials and Applications
- Advanced Condensed Matter Physics
- Molecular Junctions and Nanostructures
- Rare-earth and actinide compounds
- Perovskite Materials and Applications
- N-Heterocyclic Carbenes in Organic and Inorganic Chemistry
University of Göttingen
2023-2024
Brookhaven National Laboratory
2000
Florida State University
1994-1995
National High Magnetic Field Laboratory
1995
The oxygen-deficient double perovskite YBaCo2O5, containing corner-linked CoO5 square pyramids as principal building units, undergoes a paramagnetic to antiferromagnetic spin ordering at 330 K. This is accompanied by tetragonal orthorhombic distortion. Below 220 K orbital and long-range Co(2+)/Co(3+) charge occur well change in the Co2+ state from low high spin. transition shown be very sensitive oxygen content of sample. To our knowledge this first observation spin-state induced ordering.
Strain engineering beyond substrate limitation of colossal magnetoresistant thin (La0.6Pr0.4)0.7Ca0.3MnO3 (LPCMO) films on LaAlO3-buffered SrTiO3 (LAO/STO) substrates has been demonstrated using metalorganic aerosol deposition technique. By growing partially relaxed 7-27 nm thick heteroepitaxial LAO buffer layers STO a perfect lattice matching to the LPCMO achieved. As result, strain-free 10-20 LPCMO/LAO/STO with bulk-like ferromagnetic metallic ground state were obtained. Without coherently...
We have measured the ac heat capacity of organic conductor α-(BEDT-TTF)2MHg(SCN)4 (for M = K, Rb) via a low addenda optically heated calorimetric method. find, contrary to previous reports, rise ΔC in near transition temperature TDW. The BCS parameter ΔCγTc for transitions ranges from 7.5 0.1 depending on different estimates electronic density states. Nevertheless, results are consistent with opening wave gap at TDW open orbit band, and reconstruction closed band lower temperatures.
<title>Abstract</title> Chromium telluride (Cr<sub>(1+δ)</sub>Te<sub>2</sub>) thin films of various δ were prepared using a hybrid pulsed laser deposition technique by varying the flux rate Te-molecular beam source. We found that thickness and nanocrystalline quality increased with Te-flux. All three showed hexagonal layering same out-of-plane lattice constant. Increasing Te-flux stabilized CrTe, Cr<sub>2</sub>Te<sub>3</sub>, CrTe<sub>2</sub> phases telluride, they different magnetic...
X-ray photoelectron spectroscopy (XPS) is a versatile tool for identifying the chemical and electronic state of an element. However, presence various initial- final-state effects makes interpretation XPS spectra tricky erroneous. Metal oxides show multipeak when charge carriers are coupled with core hole photoion after photoemission. The extra peaks often misconstrued to originate from other oxidation states cation. With systematic approach analysis Nb 3d partially oxidized NbOx thin films...
Ultrafast optical excitations allow creating new metastable and hidden states in quantum materials. However, the fundamental material properties required to support emergent order are largely unknown. Here, we show for two colossal magnetoresistive (CMR) manganites that electronic phase separation (EPS) strongly favors nonthermal behavior exploit this stabilize an optically induced conducting state. Our results shed light on role of EPS control CMR provide guidance design materials can...
In this Letter, we present investigations of thermal transport in (LaMnO$_3$)$_n$/(SrMnO$_3$)$_n$ superlattices (SLs) with SL periods $Λ=2n$ between $2$ and $12$ unit cells. The analysis the experimental data clearly reveals a minimum conductivity $κ$ at $Λ=6$ u.c. Furthermore, theoretically estimate phonon mean free path to be about $3Λ$ our SLs. These findings show that, wide temperature range $\pm 100\,$K around room temperature, manganite SLs is coherent. addition, demonstrate that...
Abstract pe have measured the low temperature transport and magnetic behavior in α-(BEDTTTF) 2 RbHg(SCN) 4 [alpha-bis(ethylenedithio) tetrathiafulvalene-rubidium-mercurp-thiocpanate]. Below 12 K this material is believed to go into a spin density pave state. At lower temperatures, below 1 K, further transition resistance state occurs, which may be tendency for superconductivity. We determined corresponding T - H phase diagram new state, report shielding experiments show less than 0.1%...
Ultrafast optical excitations allow creating new metastable and hidden states in quantum materials. However, the fundamental material properties required to support emergent order are largely unknown. Here we show for two colossal magnetoresistive (CMR) manganites that electronic phase separation (EPS) strongly favors non-thermal behavior exploit this stabilize an optically-induced conducting state. Our results shed light on role of EPS control CMR provide guidance design materials can...