English
Related papers

Related papers: Valley-based FETs in graphene

200 papers

We show how the trigonal warping effect in doped graphene can be used to produce fully valley polarized currents. We propose a device that acts both as a beam splitter and a collimator of these electronic currents. The result is…

Mesoscale and Nanoscale Physics · Physics 2007-10-05 J. L. Garcia-Pomar , A. Cortijo , M. Nieto-Vesperinas

The existence of nontrivial Berry phases associated with two inequivalent valleys in graphene provides interesting opportunities for investigating the valley-projected topological states. Examples of such studies include observation of…

Mesoscale and Nanoscale Physics · Physics 2020-05-13 C. -C. Hsu , M. L. Teague , J. -Q. Wang , N. -C. Yeh

The valley degree of freedom in 2D materials can be manipulated for low-dissipation quantum electronics called valleytronics. At the boundary between two regions of bilayer graphene with different atomic or electrostatic configuration,…

Mesoscale and Nanoscale Physics · Physics 2024-04-03 Konstantin Davydov , Xi Zhang , Wei Ren , Matthew Coles , Logan Kline , Bryan Zucker , Kenji Watanabe , Takashi Taniguchi , Ke Wang

The interplay of massive electrons with spin-orbit coupling in bulk graphene results in a spin-valley dependent gap. Thus, a barrier with such properties can act as a filter, transmitting only opposite spins from opposite valleys. In this…

Mesoscale and Nanoscale Physics · Physics 2014-07-25 Marko M. Grujić , Milan Ž. Tadić , François M. Peeters

It is quite easy to control spin polarization and spin direction of a system via magnetic fields. However, there is no such a direct and efficient way to manipulate valley pseudospin degree of freedom. Here, we demonstrate experimentally…

Mesoscale and Nanoscale Physics · Physics 2020-03-18 Si-Yu Li , Ying Su , Ya-Ning Ren , Lin He

We show that the optical excitation of graphene with polarized light leads to the pure valley current where carriers in the valleys counterflow. The current in each valley originates from asymmetry of optical transitions and electron…

Mesoscale and Nanoscale Physics · Physics 2015-05-28 L. E. Golub , S. A. Tarasenko , M. V. Entin , L. I. Magarill

We test the valley-filtering capabilities of a quantum dot inscribed by locally straining an $\alpha$-$\mathcal{T}_3$ lattice. Specifically, we consider an out-of-plane Gaussian bump in the center of a four-terminal configuration and…

Mesoscale and Nanoscale Physics · Physics 2021-04-16 Alexander Filusch , Alan R. Bishop , Avadh Saxena , Gerhard Wellein , Holger Fehske

We study the electronic transport properties at the intersection of three topological zero-lines as the elementary current partition node that arises in minimally twisted bilayer graphene. Unlike the partition laws of two intersecting…

Mesoscale and Nanoscale Physics · Physics 2020-09-02 Tao Hou , Yafei Ren , Yujie Quan , Jeil Jung , Wei Ren , Zhenhua Qiao

In multivalley semiconductors, the valley degree of freedom can be potentially used to store, manipulate and read quantum information, but its control remains challenging. The valleys in bilayer graphene can be addressed by a perpendicular…

We predict the coexistence of tunneling spin and valley Hall effects when electrons in graphene coherently transmit through a barrier with the broken inversion symmetry and proximity-induced spin-orbit coupling. Due to the rotation of the…

Mesoscale and Nanoscale Physics · Physics 2025-02-20 W. Zeng

We propose how to form spin qubits in graphene. A crucial requirement to achieve this goal is to find quantum dot states where the usual valley degeneracy in bulk graphene is lifted. We show that this problem can be avoided in quantum dots…

Mesoscale and Nanoscale Physics · Physics 2007-05-23 B. Trauzettel , Denis V. Bulaev , Daniel Loss , Guido Burkard

Topologically protected zero-line modes appear at the interface between two regions of the monolayer graphene in quantum anomalous Hall phase with different Chern number. In the presence of staggered sublattice potential, the band gaps of…

Mesoscale and Nanoscale Physics · Physics 2019-02-20 Ma Luo

Vertical tunneling field-effect-transistor (FET) based on graphene heterojunctions with layers of hBN is simulated by self-consistent quantum transport simulations. It is found that the asymmetric p-type and n-type conduction is due to work…

Mesoscale and Nanoscale Physics · Physics 2015-06-05 S. Bala Kumar , Gyungseon Seol , Jing Guo

We explore a solid state qubit defined on valley isospin of an electron confined in a gate-defined quantum dot created in an area of monolayer MoS$_2$/WS$_2$ lateral junction, where a steep dipolar potential emerges. We show that the…

Mesoscale and Nanoscale Physics · Physics 2024-08-20 Jarosław Pawłowski , John Eric Tiessen , Rockwell Dax , Junxia Shi

Valley degree of freedom besides spin is a promising candidate as a carrier of information. Spintronics has come a long way and spin modulation can be realized by quantum interference and spin-orbit coupling effect. However, the control of…

Mesoscale and Nanoscale Physics · Physics 2025-08-08 Hui-Ying Mu , Nie-Wei Wang , Ying-Na Du , Xing-Tao An , Jian-Jun Liu

Developing alternative paradigms of electronics beyond silicon technology requires the exploration of fundamentally new physical mechanisms, such as the valley specific phenomena in hexagonal two-dimensional materials. We realize ballistic…

Mesoscale and Nanoscale Physics · Physics 2018-12-11 Jing Li , Rui-Xing Zhang , Zhenxi Yin , Jianxiao Zhang , Kenji Watanabe , Takashi Taniguchi , Chaoxing Liu , Jun Zhu

Recent experiments have revealed that novel nonequilibrium states consistent with the hydrodynamic description of electrons are realized in ultrapure graphene, which hosts the valley degrees of freedom. Here, we formulate a theory of…

Mesoscale and Nanoscale Physics · Physics 2022-05-05 Ryotaro Sano , Daigo Oue , Mamoru Matsuo

The aim of presented research is to design a nanodevice, based on a MoS$_2$ monolayer, performing operations on a well-defined valley qubit. We show how to confine an electron in a gate induced quantum dot within the monolayer, and to…

Mesoscale and Nanoscale Physics · Physics 2018-05-24 J. Pawłowski , D. Żebrowski , S. Bednarek

We consider tunneling transport between two parallel graphene sheets where one is a single-layer sample and the other one a bilayer. In the presence of an in-plane magnetic field, the interplay between combined energy and momentum…

Mesoscale and Nanoscale Physics · Physics 2014-02-25 L Pratley , U. Zuelicke

Dirac electrons in graphene have a valley degree of freedom that is being explored as a carrier of information. In that context of "valleytronics" one seeks to coherently manipulate the valley index. Here we show that reflection from a…

Mesoscale and Nanoscale Physics · Physics 2018-09-12 C. W. J. Beenakker , N. V. Gnezdilov , E. Dresselhaus , V. P. Ostroukh , Y. Herasymenko , I. Adagideli , J. Tworzydlo