Zobrazeno 1 - 10
of 102
pro vyhledávání: '"Ahlers, Franz"'
Autor:
Pakdehi, Davood Momeni, Pierz, Klaus, Wundrack, Stefan, Aprojanz, Johannes, Nguyen, Thi Thuy Nhung, Dziomba, Thorsten, Hohls, Frank, Bakin, Andrey, Stosch, Rainer, Tegenkamp, Christoph, Ahlers, Franz J., Schumacher, Hans W.
Publikováno v:
ACS Appl. Nano Mater. 2019, 2, 2, 844-852
In this study, we first show that the argon flow during epitaxial graphene growth is an important parameter to control the quality of the buffer and the graphene layer. Atomic force microscopy (AFM) and low-energy electron diffraction (LEED) measurem
Externí odkaz:
http://arxiv.org/abs/1811.04998
Autor:
Goetz, Martin, Fijalkowski, Kajetan M., Pesel, Eckart, Hartl, Matthias, Schreyeck, Steffen, Winnerlein, Martin, Grauer, Stefan, Scherer, Hansjoerg, Brunner, Karl, Gould, Charles, Ahlers, Franz J., Molenkamp, Laurens W.
Publikováno v:
Appl. Phys. Lett. 112, 072102 (2018)
In the quantum anomalous Hall effect, the edge states of a ferromagnetically doped topological insulator exhibit quantized Hall resistance and dissipationless transport at zero magnetic field. Up to now, however, the resistance was experimentally ass
Externí odkaz:
http://arxiv.org/abs/1710.04090
We present precision measurements of the fractional quantized Hall effect where the quantized resistance $R^{[1/3]}$ in the fractional quantum Hall state at filling factor 1/3 was compared with a quantized resistance $R^{[2]}$, represented by an inte
Externí odkaz:
http://arxiv.org/abs/1703.05213
Autor:
Kalmbach, Cay-Christian, Ahlers, Franz Josef, Schurr, Jürgen, Müller, André, Feilhauer, Juraj, Kruskopf, Mattias, Pierz, Klaus, Hohls, Frank, Haug, Rolf J.
Publikováno v:
Phys. Rev. B 94, 205430 (2016)
We investigate the 1/f noise properties of epitaxial graphene devices at low temperatures as a function of temperature, current and magnetic flux density. At low currents, an exponential decay of the 1/f noise power spectral density with increasing t
Externí odkaz:
http://arxiv.org/abs/1609.04950
Autor:
Kruskopf, Mattias, Pakdehi, Davood Momeni, Pierz, Klaus, Wundrack, Stefan, Stosch, Rainer, Dziomba, Thorsten, Goetz, Martin, Baringhaus, Jens, Aprojanz, Johannes, Tegenkamp, Christoph, Lidzba, Jakob, Seyller, Thomas, Hohls, Frank, Ahlers, Franz J., Schumacher, Hans W.
We present a new fabrication method for epitaxial graphene on SiC which enables the growth of ultra-smooth defect- and bilayer-free graphene sheets with an unprecedented reproducibility, a necessary prerequisite for wafer-scale fabrication of high qu
Externí odkaz:
http://arxiv.org/abs/1606.01709
Autor:
Stein, Friederike, Drung, Dietmar, Fricke, Lukas, Scherer, Hansjörg, Hohls, Frank, Leicht, Christoph, Götz, Martin, Krause, Christian, Behr, Ralf, Pesel, Eckart, Pierz, Klaus, Siegner, Uwe, Ahlers, Franz-Josef, Schumacher, Hans W.
Publikováno v:
Appl. Phys. Lett. 107, 103501 (2015)
We report on high-accuracy measurements of quantized current, sourced by a tunable-barrier single-electron pump at frequencies $f$ up to $1$ GHz. The measurements were performed with a new picoammeter instrument, traceable to the Josephson and quantu
Externí odkaz:
http://arxiv.org/abs/1506.05965
Autor:
Kruskopf, Mattias, Pierz, Klaus, Wundrack, Stefan, Stosch, Rainer, Dziomba, Thorsten, Kalmbach, Cay-Christian, Müller, André, Baringhaus, Jens, Tegenkamp, Christoph, Ahlers, Franz J., Schumacher, Hans W.
Publikováno v:
J.Phys.: Condens. Matter 27 (2015) 185303
The electrical transport properties of epitaxial graphene layers are correlated with the SiC surface morphology. In this study we show by atomic force microscopy and Raman measurements that the surface morphology and the structure of the epitaxial gr
Externí odkaz:
http://arxiv.org/abs/1502.03927
An ultrastable low-noise current amplifier (ULCA) is presented. The ULCA is a non-cryogenic instrument based on specially designed operational amplifiers and resistor networks. It involves two stages, the first providing a 1000-fold current gain and
Externí odkaz:
http://arxiv.org/abs/1408.5088
Autor:
Matei, Dan G., Weber, Nils-Eike, Kurasch, Simon, Wundrack, Stefan, Woszczyna, Miroslaw, Grothe, Miriam, Weimann, Thomas, Ahlers, Franz, Stosch, Rainer, Kaiser, Ute, Turchanin, Andrey
Publikováno v:
Adv. Mater. 25, 4146-4151 (2013)
We demonstrate how self-assembled monolayers of aromatic molecules on copper substrates can be converted into high-quality single-layer graphene using low-energy electron irradiation and subsequent annealing. We characterize this two-dimensional soli
Externí odkaz:
http://arxiv.org/abs/1406.1962
Autor:
Woszczyna, Miroslaw, Winter, Andreas, Grothe, Miriam, Willunat, Annika, Wundrack, Stefan, Stosch, Rainer, Weimann, Thomas, Ahlers, Franz, Turchanin, Andrey
Publikováno v:
Advanced Materials 28 (2014) 4831-4837
We present a route to non-destructive functionalization of graphene via assembly of vertical all-carbon van der Waals heterostructures. To this end, we employ singlelayer graphene (SLG) sheets grown by low-pressure methane CVD on Cu foils and large-a
Externí odkaz:
http://arxiv.org/abs/1406.1966