| Autor: |
Kim K; Microelectronics Research Center, Department of Electrical and Computer Engineering , The University of Texas at Austin , Austin , Texas 78758 , United States., Prasad N; Microelectronics Research Center, Department of Electrical and Computer Engineering , The University of Texas at Austin , Austin , Texas 78758 , United States., Movva HCP; Microelectronics Research Center, Department of Electrical and Computer Engineering , The University of Texas at Austin , Austin , Texas 78758 , United States., Burg GW; Microelectronics Research Center, Department of Electrical and Computer Engineering , The University of Texas at Austin , Austin , Texas 78758 , United States., Wang Y; Microelectronics Research Center, Department of Electrical and Computer Engineering , The University of Texas at Austin , Austin , Texas 78758 , United States., Larentis S; Microelectronics Research Center, Department of Electrical and Computer Engineering , The University of Texas at Austin , Austin , Texas 78758 , United States., Taniguchi T; National Institute for Materials Science , 1-1 Namiki , Tsukuba , Ibaraki 305-0044 , Japan., Watanabe K; National Institute for Materials Science , 1-1 Namiki , Tsukuba , Ibaraki 305-0044 , Japan., Register LF; Microelectronics Research Center, Department of Electrical and Computer Engineering , The University of Texas at Austin , Austin , Texas 78758 , United States., Tutuc E; Microelectronics Research Center, Department of Electrical and Computer Engineering , The University of Texas at Austin , Austin , Texas 78758 , United States. |
| Abstrakt: |
We investigate interlayer tunneling in heterostructures consisting of two tungsten diselenide (WSe 2 ) monolayers with controlled rotational alignment, and separated by hexagonal boron nitride. In samples where the two WSe 2 monolayers are rotationally aligned we observe resonant tunneling, manifested by a large conductance and negative differential resistance in the vicinity of zero interlayer bias, which stem from energy- and momentum-conserving tunneling. Because the spin-orbit coupling leads to coupled spin-valley degrees of freedom, the twist between the two WSe 2 monolayers allows us to probe the conservation of spin-valley degree of freedom in tunneling. In heterostructures where the two WSe 2 monolayers have a 180° relative twist, such that the Brillouin zone of one layer is aligned with the time-reversed Brillouin zone of the opposite layer, the resonant tunneling between the layers is suppressed. These findings provide evidence that, in addition to momentum, the spin-valley degree of freedom is also conserved in vertical transport. |
