Zobrazeno 1 - 10
of 62
pro vyhledávání: '"Volmer, Frank"'
Autor:
Volmer, Frank, Ersfeld, Manfred, Junior, Paulo E. Faria, Waldecker, Lutz, Parashar, Bharti, Rathmann, Lars, Dubey, Sudipta, Cojocariu, Iulia, Feyer, Vitaliy, Watanabe, Kenji, Taniguchi, Takashi, Schneider, Claus M., Plucinski, Lukasz, Stampfer, Christoph, Fabian, Jaroslav, Beschoten, Bernd
Publikováno v:
npj 2D Mater. Appl. 7, 58 (2023)
We identify an optical excitation mechanism that transfers a valley polarization from photo-excited electron-hole pairs to free charge carriers in twisted WSe$_2$/MoSe$_2$ heterobilayers. For small twist angles, the valley lifetimes of the charge car
Externí odkaz:
http://arxiv.org/abs/2211.17210
Autor:
Volmer, Frank, Seidler, Inga, Bisswanger, Timo, Tu, Jhih-Sian, Schreiber, Lars R., Stampfer, Christoph, Beschoten, Bernd
Publikováno v:
J. Phys. D: Appl. Phys. 54, 225304 (2021)
We discuss how the emission of electrons and ions during electron-beam-induced physical vapor deposition can cause problems in micro- and nanofabrication processes. After giving a short overview of different types of radiation emitted from an electro
Externí odkaz:
http://arxiv.org/abs/2010.06459
Autor:
Ersfeld, Manfred, Volmer, Frank, Rathmann, Lars, Kotewitz, Luca, Heithoff, Maximilian, Lohmann, Mark, Yang, Bowen, Watanabe, Kenji, Taniguchi, Takashi, Bartels, Ludwig, Shi, Jing, Stampfer, Christoph, Beschoten, Bernd
Publikováno v:
Spintronics XIII 11470, 114702M (2020)
One of the main tasks in the investigation of 2-dimensional transition metal dichalcogenides is the determination of valley lifetimes. In this work, we combine time-resolved Kerr rotation with electrical transport measurements to explore the gate-dep
Externí odkaz:
http://arxiv.org/abs/2007.14712
Autor:
Ersfeld, Manfred, Volmer, Frank, Rathmann, Lars, Kotewitz, Luca, Heithoff, Maximilian, Lohmann, Mark, Yang, Bowen, Watanabe, Kenji, Taniguchi, Takashi, Bartels, Ludwig, Shi, Jing, Stampfer, Christoph, Beschoten, Bernd
We report on nanosecond long, gate-dependent valley lifetimes of free charge carriers in monolayer WSe$_2$, unambiguously identified by the combination of time-resolved Kerr rotation and electrical transport measurements. While the valley polarizatio
Externí odkaz:
http://arxiv.org/abs/1911.11692
Autor:
Jafarpisheh, Shaham, Volmer, Frank, Wang, Zhiwei, Canto, Bárbara, Ando, Yoichi, Stampfer, Christoph, Beschoten, Bernd
The spin-polarized surface states in topological insulators offer unique transport characteristics which make them distinguishable from trivial conductors. Due to the topological protection, these states are gapless over the whole surface of the mate
Externí odkaz:
http://arxiv.org/abs/1907.10347
Autor:
Drögeler, Marc, Banszerus, Luca, Volmer, Frank, Taniguchi, Takashi, Watanabe, Kenji, Beschoten, Bernd, Stampfer, Christoph
Publikováno v:
Appl. Phys. Lett. 111, 152402 (2017)
Integrating high-mobility graphene grown by chemical vapor deposition (CVD) into spin transport devices is one of the key tasks in graphene spintronics. We use a van der Waals pickup technique to transfer CVD graphene by hexagonal boron nitride (hBN)
Externí odkaz:
http://arxiv.org/abs/1709.01364
Autor:
Ersfeld, Manfred, Volmer, Frank, de Melo, Pedro Miguel M. C., de Winter, Robin, Heithoff, Maximilian, Zanolli, Zeila, Stampfer, Christoph, Verstraete, Matthieu J., Beschoten, Bernd
Publikováno v:
Nano Lett. 19, 4083 (2019)
We present time-resolved Kerr rotation measurements, showing spin lifetimes of over 100 ns at room temperature in monolayer MoSe$_2$. These long lifetimes are accompanied by an intriguing temperature dependence of the Kerr amplitude, which increases
Externí odkaz:
http://arxiv.org/abs/1708.00228
Publikováno v:
Physica Status Solidi (b), 1700293 (2017)
Spin transport properties of graphene non-local spin valve devices are typically determined from Hanle spin precession measurements by using a simplified solution of the one-dimensional Bloch-Torrey equation which assumes infinitely long transport ch
Externí odkaz:
http://arxiv.org/abs/1706.09807
Autor:
Drögeler, Marc, Franzen, Christopher, Volmer, Frank, Pohlmann, Tobias, Banszerus, Luca, Wolter, Maik, Watanabe, Kenji, Taniguchi, Takashi, Stampfer, Christoph, Beschoten, Bernd
Publikováno v:
Nano Lett. 16, 3533 (2016)
We show spin lifetimes of 12.6 ns and spin diffusion lengths as long as 30.5 \mu m in single layer graphene non-local spin transport devices at room temperature. This is accomplished by the fabrication of Co/MgO-electrodes on a Si/SiO$_2$ substrate a
Externí odkaz:
http://arxiv.org/abs/1602.02725
Autor:
Drögeler, Marc, Volmer, Frank, Wolter, Maik, Watanabe, Kenji, Taniguchi, Takashi, Neumaier, Daniel, Stampfer, Christoph, Beschoten, Bernd
Publikováno v:
Physica Status Solidi (b) 252, 2395 (2015)
We present spin transport studies on bi- and trilayer graphene non-local spin-valves which have been fabricated by a bottom-up fabrication method. By this technique, spin injection electrodes are first deposited onto Si$^{++}$/SiO$_2$ substrates with
Externí odkaz:
http://arxiv.org/abs/1507.02677