Hall effect in cobalt-doped TiO2−δ_{2-\delta}

We report Hall effect measurements on thin films of cobalt-doped TiO$_{2-\delta}$. Films with low carrier concentrations (10$^{18}$ - 10$^{19}$) yield a linear behavior in the Hall data while those having higher carrier concentrations (10$^{21}$ - 10$^{22}$) display anomalous behavior near zero field. In the entire range of carrier concentration, n-type conduction is observed. The appearance of the anomalous behavior is accompanied by a possible structural change from rutile TiO$_{2}$ to Ti_[n}O$_{2n-1}$ Magneli phase(s)

Optical band edge shift of anatase cobalt-doped titanium dioxide

We report on the optical properties of magnetic cobalt-doped anatase phase titanium dioxide Ti_{1-x}Co_{x}O_{2-d} films for low doping concentrations, 0 <= x <= 0.02, in the spectral range 0.2 to 5 eV. For well oxygenated films (d << 1) the optical conductivity is characterized by an absence of optical absorption below an onset of interband transitions at 3.6 eV and a blue shift of the optical band edge with increasing Co concentration. The absence of below band gap absorption is inconsistent with theoretical models which contain midgap magnetic impurity bands and suggests that strong on-site Coulomb interactions shift the O-band to Co-level optical transitions to energies above the gap.Comment: 5 pages, 4 figures, 1 table; Version 2 - major content revisio

Floristic studies on some rare plants in Western Ghats of Nasik District, M. S.

The present study deals with taxonomical aspects along with the observation regarding threats, flowering and fruiting period, precise locations of some rare plants of Western Ghats in Nasik District of Maharashtra. Extensive field visits and botanical excursions were conducted during period of investigation i. e. from 2013-2019 in and around the forest area of Nashik district. The major areas that were explored during study are mainly forest pockets and hills regions of Trimbakeshwar, Brahmhagiri mountains, Anjaneri hills, Adwadi hills, Sinnar and environs hilly ranges, Kelzar hilly areas, Mulher, Salher, etc. During the study: more than 150 species of rare plants belonging to 46 families were recorded. The probable reasons that were observe from the decrease of rare plant species population are destruction of natural habitats due to increasing illegal acquiring of forest land, massive deforestation and rapid urbanization. Also, ex-situ conservation of some plant species within the college botanical garden was attempted. However: the present study highlights an effective and purposeful conservation strategy to be adopted for the sustainable use and conservation of important rare plants in the region

Length-Weight Relationship in Salmostoma navacula and Channa muralius Godavari River at Kaigaon Toka, Dist. Aurangabad (M.S.) India

The length-weight relationship of Salmostoma navacula and Channa muralius were studied Godavari River at Kaigaon Toka from January 2010 to December 2010. The exponential value of fishes indicates allometric growth pattern in the natural habitat. The logarithmatic regression equation obtained in Salmostoma navacula was log W = -0.531+1.70 LogL and in Channa muralius was Log W = -0.067+1.45 LogL. The coefficient of correlation in Salmostoma navacula was r = 0.711 and in Channa muralius was r = 0.967. Which shows the correlation factor revealed positive correlation between length and weight

Thermal hysteresis of microwave loss in (La1-xPrx)(0.7)Ca 0.3MnO3 films

[EN] We have measured the temperature (T) dependencies of the dc resistances (R-dc) and the microwave loss (R-muw) in a variety of samples of (La1-xPrx)(0.7)Ca0.3MnO3 while varying x from 0 to 0.4. Whereas both the sets of data exhibit maxima, the ac loss peak is much flatter and, during cooling, appears at a much lower temperature than the peak temperature in R-dc. The discrepancy, which vanishes for x=0, increases with lowering tolerance factor (t) (or increasing x). Also R-muw vs T exhibits large thermal hysteresis for x=0.4 indicating that the transition is first order. Cooling in a magnetic field of 9 kOe causes an upward shift of about 20 K in the R-muw peak, in some of the x=0.4 films, yielding a large magnetoimpedance. Further, once these films are exposed to a magnetic field at low T, they fail to recover their virginal behavior on subsequent cooling from room T. These films could be brought to their original state by annealing at high T. The discrepancy between R-dc and R-muw implies that the system is inhomogeneous at low T, providing, for the first time, microwave absorption evidence that manganites exhibit multiphase behavior. Presumably, disorder and strain (increasing with x) combine to stabilize a mixed phase. (C) 2002 American Institute of Physics.S77367738911

Large Second Harmonic Kerr rotation in GaFeO3 thin films on YSZ buffered Silicon

Epitaxial thin films of gallium iron oxide (GaFeO3) are grown on (001) silicon by pulsed laser deposition (PLD) using yttrium-stabilized zirconia (YSZ) buffer layer. The crystalline template buffer layer is in-situ PLD grown through the step of high temperature stripping of the intrinsic silicon surface oxide. The X-ray diffraction pattern shows c-axis orientation of YSZ and b-axis orientation of GaFeO3 on Si (100) substrate. The ferromagnetic transition temperature (TC ~ 215 K) is in good agreement with the bulk data. The films show a large nonlinear second harmonic Kerr rotation of ~15 degrees in the ferromagnetic state.Comment: 16 pages, 4 figures, To be published in J. Magn. Magn. Ma

Anomalous Hall effect in Fe/Cu bilayers

The scaling of anomalous Hall resistivity on the longitudinal resistivity has been intensively studied in the different magnetic systems, including multilayers and granular films, to examine which mechanism, skew scattering or side-jump, dominates. The basis of the scaling law is that both the resistivities are due to the electron scattering at the imperfections in the materials. By studying of anomalous Hall effect (AHE) in the simple Fe/Cu bilayers, we demonstrate that the measured anomalous Hall effect should not follow the scaling laws derived from skew scattering or side-jump mechanism due to the short-circuit and shunting effects of the non-magnetic layers.Comment: 12 pages, 4 figures; http://www.springerlink.com/content/1718722u75j24587

Performance of the CMS Level-1 trigger during commissioning with cosmic ray muons and LHC beams

This is the Pre-print version of the Article. The official published version can be accessed from the link below - Copyright @ 2010 IOPThe CMS Level-1 trigger was used to select cosmic ray muons and LHC beam events during data-taking runs in 2008, and to estimate the level of detector noise. This paper describes the trigger components used, the algorithms that were executed, and the trigger synchronisation. Using data from extended cosmic ray runs, the muon, electron/photon, and jet triggers have been validated, and their performance evaluated. Efficiencies were found to be high, resolutions were found to be good, and rates as expected.This work is supported by FMSR (Austria); FNRS and FWO (Belgium); CNPq, CAPES, FAPERJ, and FAPESP (Brazil); MES (Bulgaria); CERN; CAS, MoST, and NSFC (China); COLCIENCIAS (Colombia); MSES (Croatia); RPF (Cyprus); Academy of Sciences and NICPB (Estonia); Academy of Finland, ME, and HIP (Finland); CEA and CNRS/IN2P3 (France); BMBF, DFG, and HGF (Germany); GSRT (Greece); OTKA and NKTH (Hungary); DAE and DST (India); IPM (Iran); SFI (Ireland); INFN (Italy); NRF (Korea); LAS (Lithuania); CINVESTAV, CONACYT, SEP, and UASLP-FAI (Mexico); PAEC (Pakistan); SCSR (Poland); FCT (Portugal); JINR (Armenia, Belarus, Georgia, Ukraine, Uzbekistan); MST and MAE (Russia); MSTDS (Serbia); MICINN and CPAN (Spain); Swiss Funding Agencies (Switzerland); NSC (Taipei); TUBITAK and TAEK (Turkey); STFC (United Kingdom); DOE and NSF (USA)