Zobrazeno 1 - 10
of 260
pro vyhledávání: '"Friedland, K J"'
Publikováno v:
Phys. Rev. B 86, 155309 (2012)
We analyze fluctuation of the layer thicknesses and its influence on the strain state of (In,Ga)As/(Al,Ga)As micro-tubes containing quantum well structures. In those structures a curved high-mobility two-dimensional electron gas (HM2DEG) is establish
Externí odkaz:
http://arxiv.org/abs/1907.09368
Autor:
Poux, A., Wasilewski, Z. R., Friedland, K. J., Hey, R., Ploog, K. H., Airey, R., Plochocka, P., Maude, D. K.
Publikováno v:
Phys. Rev. B 94, 075411 (2016)
Intra Landau level thermal activation, from localized states in the tail, to delocalized states above the mobility edge in the same Landau level, explains the $B_c(T)$ (half width of the dissipationless state) phase diagram for a number of different
Externí odkaz:
http://arxiv.org/abs/1609.00485
Publikováno v:
Phys. Rev. B vol. 88, 155313 (2013)
We have performed conductivity measurements on a Si-MOSFET sample with a slot in the upper gate, allowing for different electron densities n_1 and n_2 across the slot. Dynamic longitudinal resistance was measured by a standard lock-in technique, whil
Externí odkaz:
http://arxiv.org/abs/1307.6260
Publikováno v:
Europhys. Lett. vol. 97, 37002 (2012)
Positive magnetoresistance (PMR) of a silicon MOSFET in parallel magnetic fields B has been measured at high electron densities n >> n_c where n_c is the critical density of the metal-insulator transition (MIT). It turns out that the normalized PMR c
Externí odkaz:
http://arxiv.org/abs/1112.1819
Publikováno v:
Ann. Phys. (Berlin) vol. 18, pp. 913-917 (2009)
We report measurements on a Si-MOSFET sample with a slot in the upper gate, allowing for different electron densities n_{1,2} across the slot. The dynamic longitudinal resistance was measured by the standard lock-in technique, while maintaining a lar
Externí odkaz:
http://arxiv.org/abs/0909.1491
Autor:
Faugeras, C., Orlita, M., Deutschlander, S., Martinez, G., Yu, P. Y., Riedel, A., Hey, R., Friedland, K. J.
Publikováno v:
Phys. Rev. B 80, 073303, (2009)
Precise absolute far-infra-red magneto-transmission experiments have been performed in magnetic fields up to 33 T on a series of single GaAs quantum wells doped at different levels. The transmission spectra have been simulated with a multilayer diele
Externí odkaz:
http://arxiv.org/abs/0909.1212
Publikováno v:
Phys. Rev. B 2009
The quantum Hall effect is investigated in a high-mobility two-dimensional electron gas on the surface of a cylinder. The novel topology leads to a spatially varying filling factor along the current path. The resulting inhomogeneous current-density d
Externí odkaz:
http://arxiv.org/abs/0901.1490
The transversal and longitudinal resistance in the quantum Hall effect regime was measured in a Si MOSFET sample in which a slot-gate allows one to vary the electron density and filling factor in different parts of the sample. In case of unequal gate
Externí odkaz:
http://arxiv.org/abs/0803.4432
Autor:
Piot, B. A., Maude, D. K., Henini, M., Wasilewski, Z. R., Gupta, J. A., Friedland, K. J., Hey, R., Ploog, K. H., Gennser, U., Cavanna, A., Mailly, D., Airey, R., Hill, G.
Publikováno v:
Phys. Rev. B 75, 155332 (2007)
In a recent paper [B. A. Piot et al., Phys. Rev. B 72, 245325 (2005)], we have shown that the lifting of the electron spin degeneracy in the integer quantum Hall effect at high filling factors should be interpreted as a magnetic-field-induced Stoner
Externí odkaz:
http://arxiv.org/abs/0705.0129
Autor:
Friedland, K. -J., Hey, R., Kostial, H., Jahn, U., Wiebicke, E., Ploog, K. H., Vorob'ev, A., Yukecheva, Ju., Prinz, V.
We have fabricated high-mobility, two-dimensional electron gases in a GaAs quantum well on cylindrical surfaces, which allows to investigate the magnetotransport behavior under varying magnetic fields along the current path. A strong asymmetry in the
Externí odkaz:
http://arxiv.org/abs/cond-mat/0703665