Zobrazeno 1 - 10
of 68
pro vyhledávání: '"Heyer, O"'
Measurements of thermodynamic and transport properties of EuC$_2$: a low-temperature analogue of EuO
Publikováno v:
New Journal of Physics 13 113041 (2011)
EuC$_2$ is a ferromagnet with a Curie-temperature of $T_C \simeq 15\,$K. It is semiconducting with the particularity that the resistivity drops by about 5 orders of magnitude on cooling through $T_C$, which is therefore called a metal-insulator trans
Externí odkaz:
http://arxiv.org/abs/1103.0980
Autor:
Heyer, O., Lorenz, T., Zabolotnyy, V. B., Evtushinsky, D. V., Borisenko, S. V., Morozov, I., Harnagea, L., Wurmehl, S., Hess, C., Buechner, B.
Publikováno v:
Phys. Rev. B 84, 064512 (2011)
LiFeAs is unique among the broad family of FeAs-based superconductors, because it is superconducting with a rather large $T_c\simeq 18$ K under ambient conditions although it is a stoichiometric compound. We studied the electrical transport on a high
Externí odkaz:
http://arxiv.org/abs/1010.2876
Publikováno v:
Phys. Rev. B 83, 024418 (2011)
The crystal structure and the magnetism of BaMn$_2$O$_3$ have been studied by thermodynamic and by diffraction techniques using large single crystals and powders. BaMn$_2$O$_3$ is a realization of a $S = 5/2$ spin ladder as the magnetic interaction i
Externí odkaz:
http://arxiv.org/abs/1010.1183
Autor:
Forthaus, M. K., Sengupta, K., Heyer, O., Christensen, N. E., Svane, A., Syassen, K., Khomskii, D. I., Lorenz, T., Abd-Elmeguid, M. M.
Publikováno v:
Phys. Rev. Lett. 105, 157001 (2010)
We found that under pressure SnO with alpha-PbO structure, the same structure as in many Fe-based superconductors, e.g. beta-FeSe, undergoes a transition to a superconducting state for p > 6 GPa with a maximum Tc of 1.4 K at p = 9.3 GPa. The pressure
Externí odkaz:
http://arxiv.org/abs/1009.3787
Autor:
Kalinov, A. V., Gorbenko, O. Yu., Taldenkov, A. N., Rohrkamp, J., Heyer, O., Jodlauk, S., Babushkina, N. A., Fisher, L. M., Kaul, A. R., Kamenev, A. A., Kuzmova, T. G., Khomskii, D. I., Kugel, K. I., Lorenz, T.
We present the study of magnetization, thermal expansion, specific heat, resistivity, and a.c. susceptibility of (Pr$_{1-y}$Eu$_y$)$_{0.7}$Ca$_{0.3}$CoO$_3$ cobaltites. The measurements were performed on ceramic samples with $y = 0.12 - 0.26$ and $y
Externí odkaz:
http://arxiv.org/abs/0909.2978
Publikováno v:
Phys. Rev. Lett. 100, 067208 (2008)
We present high-resolution measurements of the $c^\star$-axis thermal expansion and magnetostriction of piperidinium copper bromide \hp. The experimental data at low temperatures is well accounted for by a two-leg spin-ladder Hamiltonian. The thermal
Externí odkaz:
http://arxiv.org/abs/0711.1510
Autor:
Rohrkamp, J., Heyer, O., Fickenscher, T., Poettgen, R., Jodlauk, S., Hartmann, H., Lorenz, T., Mydosh, J. A.
Publikováno v:
J. Phys.: Condens. Matter 19, 486204 (2007)
We report measurements of the thermal expansion for two Eu$^{+2}$- and two Gd$^{+3}$-based intermetallics which exhibit ferro- or antiferromagnetic phase transitions. These materials show sharp positive (EuAgMg and GdAuMg) and negative (EuAuMg and Gd
Externí odkaz:
http://arxiv.org/abs/0708.2817
Publikováno v:
J. Magn. Magn. Mat. 310, 1374 (2007)
TlCuCl3 shows a quantum phase transition from a spin-gap phase to a Neel-ordered ground state as a function of magnetic field around H_{C0}~4.8T. From measurements of the specific heat c and the linear thermal expansion alpha_i we calculate the Gruen
Externí odkaz:
http://arxiv.org/abs/cond-mat/0610487
Publikováno v:
J. Magn. Magn. Mat. 316, 291 (2007)
We present thermal expansion alpha, magnetostriction and specific heat C measurements of \tal, which shows a quantum phase transition from a spin-gap phase to a Neel-ordered ground state as a function of magnetic field around H_{C0}->4.8T. Using Ehre
Externí odkaz:
http://arxiv.org/abs/cond-mat/0609348
Autor:
Heyer, O., Hollmann, N., Klassen, I., Jodlauk, S., Bohaty, L., Becker, P., Mydosh, J. A., Lorenz, T., Khomskii, D.
Publikováno v:
J. Phys.:Condens. Matter 18 (2006) L471-L475
We report the multiferroic behaviour of MnWO$_4$, a magnetic oxide with monoclinic crystal structure and spiral long-range magnetic order. Based upon recent theoretical predictions MnWO$_4$ should exhibit ferroelectric polarization coexisting with th
Externí odkaz:
http://arxiv.org/abs/cond-mat/0608498