相关论文: Al$_2$O$_3$-CaO macroporous ceramics containing hy…
Changes in crystalline phases resulting from low-temperature ageing of different yttria doped and non-doped zirconia-toughened alumina composites and nanocomposites were investigated under controlled humidity and temperature conditions in…
Aluminum-Copper (Al-Cu) alloys are essential materials for weight reduction critical structures in the aerospace and automotive industries, yet achieving their maximum ultrahigh-strength potential remains limited by nanoscale defect control…
Magnetic measurements up to 1000 K have been performed on hydrothermally synthesized $\alpha$-Fe$_{2}$O$_{3}$ nanoparticles (60 nm) using a Quantum Design vibrating sample magnetometer. A high vacuum environment (1$\times$10$^{-5}$ torr)…
At the Department of Electron Devices a cheap, more or less CMOS process compatible capacitive type RH sensor has been developed. Capacitive sensors are based on dielectric property changes of thin films upon water vapour uptake which…
In the present work, we have reported the temperature dependent thermopower ($\alpha$) behavior of La$_{0.75}$Ba$_{0.25}$CoO$_{3}$ compound in the temperature range 300-600 K. Using the Heikes formula, the estimated value of $\alpha$…
High harmonic generation from Pr$_{0.8}$Ca$_{0.2}$MnO$_{3}$ was investigated across a high-temperature paramagnetic phase and a low-temperature ferromagnetic phase. As the temperature decreases, the harmonic intensity gradually increases in…
Structural, impedance, ferroelectric and magnetic properties were examined in multiferroic Bi_{2}Fe_{4(1-x)}Co_{4x}O_{9} (0$\leq$x$\leq$0.02) ceramics synthesized via solid-state reaction method. X-ray diffraction analysis and Rietveld…
Temperature dependent electrical resistivity, crystal structure and heat capacity measurements reveal a resistivity drop and metal to semiconductor transition corresponding to first order structural phase transition near 400 K in Ca3Co4O9.…
The IR optical absorption (0.1-1.5 eV) in the $La_{0.7}Ca_{0.3}MnO_3$ films on LAO substrate exhibits the drastic temperature evolution of the spectral weight evidencing the insulator to metal transition. Single crystal films were found to…
We report the measurements of thermopower, electrical resistivity and thermal conductivity in a complex cobalt oxide Li$_{0.48}$Na$_{0.35}$CoO$_{2}$, whose crystal structure can be viewed as an intergrowth of the O3 phase of…
We report the decomposition of La2-xSrxCuO4 into La2O3 and Cu nanoparticles in ultra-high vacuum, observed by in-situ heating experiments in a transmission electron microscope (TEM). The analysis of electron diffraction data reveals that…
Conventional drying of colloidal materials and gels (including cement) can lead to detrimental effects due to the buildup of internal stresses as water evaporates from the nano/microscopic pores. However, the underlying nanoscopic…
Films of Cu-K-In-Se were co-evaporated at varied K/(K+Cu) compositions and substrate temperatures (with constant (K+Cu)/In ~ 0.85). Increased Na composition on the substrate's surface and decreased growth temperature were both found to…
The formation of solid calcium carbonate (CaCO3) from aqueous solutions or slurries containing calcium and carbon dioxide (CO2) is a complex process of considerable importance in the ecological, geochemical and biological areas. Moreover,…
We report thermal-expansion, lattice-constant, and specific-heat data of the series La_1-xA_xCoO_3 for 0<= x <= 0.30 with A = Ca, Sr, and Ba. For the undoped compound LaCoO_3 the thermal-expansion coefficient alpha(T) exhibits a pronounced…
The influence of growth regimes of the silicon capping layer on the optical properties of heterostructures with submonolayer InAs quantum dots embedded in a silicon matrix has been studied. The photoluminescence signal at 1650 nm from…
Colossal enhancement of magnetoresistance has been achieved over a broad temperature range which extends upto the room temperature, in ferromagnetic metal-charge ordered insulator manganite multi-layers. The artificially created phase…
Homogeneous face-centered cubic (fcc) polycrystalline CoCrFeNi films were deposited at room temperature on (0001)alpha-Al2O3 (c-sapphire). Phase and morphological stability of 200 to 670 nm thick films were investigated between 973 K and…
We study a frustrated quantum Ising model relevant for Ca$_3$Co$_2$O$_6$ that consists of a triangular lattice of weakly-coupled ferromagnetic (FM) chains. According to our quantum Monte Carlo simulations, the chains become FM and form a…
Nanocrystalline materials are well known for their beneficial mechanical and physical properties. However, it is of utmost importance to stabilize the microstructure at elevated temperatures to broaden the window of application e.g. by…