High mobility quasi two-dimensional electron gas(2DEG)found at the CaZrO_(3)/SrTiO_(3) nonpolar heterointerface is attractive and provides a platform for the development of functional devices and nanoelectronics.Here ...High mobility quasi two-dimensional electron gas(2DEG)found at the CaZrO_(3)/SrTiO_(3) nonpolar heterointerface is attractive and provides a platform for the development of functional devices and nanoelectronics.Here we report that the carrier density and mobility at low temperature can be tuned by gate voltage at the CaZrO_(3)/SrTiO_(3) interface.Furthermore,the magnitude of Rashba spin-orbit interaction can be modulated and increases with the gate voltage.Remarkably,the diffusion constant and the spin-orbit relaxation time can be strongly tuned by gate voltage.The diffusion constant increases by a factor of~19.98 and the relaxation time is reduced by a factor of over three orders of magnitude while the gate voltage is swept from-50 V to 100 V.These findings not only lay a foundation for further understanding the underlying mechanism of Rashba spin-orbit coupling,but also have great significance in developing various oxide functional devices.展开更多
The traditional game of cops and robbers is played on undirected graph. Recently, the same game played on directed graph is getting attention by more and more people. We knew that if we forbid some subgraph we can bou...The traditional game of cops and robbers is played on undirected graph. Recently, the same game played on directed graph is getting attention by more and more people. We knew that if we forbid some subgraph we can bound the cop number of the corresponding class of graphs. In this paper, we analyze the game of cops and robbers on H^(-)-free digraphs. However, it is not the same as the case of undirected graph. So we give a new concept(H^(-)^(*)-free digraph) to get a similar conclusion about the case of undirected graph.展开更多
基金supported by the National Natural Science Foundation of China(Grants Nos.92065110,11974048,and 12074334)。
文摘High mobility quasi two-dimensional electron gas(2DEG)found at the CaZrO_(3)/SrTiO_(3) nonpolar heterointerface is attractive and provides a platform for the development of functional devices and nanoelectronics.Here we report that the carrier density and mobility at low temperature can be tuned by gate voltage at the CaZrO_(3)/SrTiO_(3) interface.Furthermore,the magnitude of Rashba spin-orbit interaction can be modulated and increases with the gate voltage.Remarkably,the diffusion constant and the spin-orbit relaxation time can be strongly tuned by gate voltage.The diffusion constant increases by a factor of~19.98 and the relaxation time is reduced by a factor of over three orders of magnitude while the gate voltage is swept from-50 V to 100 V.These findings not only lay a foundation for further understanding the underlying mechanism of Rashba spin-orbit coupling,but also have great significance in developing various oxide functional devices.
文摘The traditional game of cops and robbers is played on undirected graph. Recently, the same game played on directed graph is getting attention by more and more people. We knew that if we forbid some subgraph we can bound the cop number of the corresponding class of graphs. In this paper, we analyze the game of cops and robbers on H^(-)-free digraphs. However, it is not the same as the case of undirected graph. So we give a new concept(H^(-)^(*)-free digraph) to get a similar conclusion about the case of undirected graph.
