English
Related papers

Related papers: Valley-based FETs in graphene

200 papers

We perform an excited state spectroscopy analysis of a silicon corner dot in a nanowire field-effect transistor to assess the electric field tunability of the valley splitting. First, we demonstrate a back-gate-controlled transition between…

The conduction properties of a grain boundary junction with Fermi velocity mismatch are analyzed. We provide a generalization of the Dirac Hamiltonian model taking into account the Fermi velocity gradient at the interface. General boundary…

Mesoscale and Nanoscale Physics · Physics 2021-01-29 Francesco Romeo

Using the tight-binding model, we investigate the valley current of the `low-bi-up' and `low-bi-low' graphene junction, where `low' and `up' are respectively the lower and upper graphene layers extended from the central AB stacking bilayer…

Mesoscale and Nanoscale Physics · Physics 2023-11-01 Ryo Tamura

The valley degeneracy of electron states in graphene stimulates intensive research of valley-related optical and transport phenomena. While many proposals on how to manipulate valley states have been put forward, experimental access to the…

Mesoscale and Nanoscale Physics · Physics 2014-11-17 L. E. Golub , S. A. Tarasenko

Valley degrees of freedom, providing a novel way to increase capacity and efficiency of information processing, have become an important instrument for photonics. Experimental studies on photonic topological valley kink states at interfaces…

We study theoretically the electron current across a monolayer graphene/hexagonal boron nitride/bilayer graphene tunnelling junction in an external magnetic field perpendicular to the layers. We show that change in effective tunnelling…

Mesoscale and Nanoscale Physics · Physics 2019-02-18 J. J . P. Thompson , D. J. Leech , M. Mucha-Kruczyński

In transition metal dichalcogenides, the valley degree of freedom directly couples valley-polarised excitons - excited by circularly polarised light - to valley-dependent chiral photons, enabling ultrafast light-driven valleytronics.…

We derive the angular generation density of photoexcited carriers in gapless and gapped Bernal bilayer graphene. Exploiting the strong anisotropy of the band structure of bilayer graphene at low energies due to trigonal warping, we show…

Mesoscale and Nanoscale Physics · Physics 2024-09-16 T. J. Osborne , M. E. Portnoi , E. Mariani

A parabolic quantum dot (QD) as realized by biasing nanostructured gates on bilayer graphene is investigated in the presence of electron-electron interaction. The energy spectrum and the phase diagram reveal unexpected transitions as…

Mesoscale and Nanoscale Physics · Physics 2015-06-18 M. Zarenia , B. Partoens , T. Chakraborty , F. M. Peeters

Two-dimensional materials with multiple degrees of freedom, including spin, valleys, and orbitals, open up an exciting avenue for engineering multifunctional devices. Beyond spintronics, these degrees of freedom can lead to novel quantum…

Mesoscale and Nanoscale Physics · Physics 2024-08-05 Md Mazharul Islam , Shamiul Alam , Md Rahatul Islam Udoy , Md Shafayat Hossain , Kathleen E Hamilton , Ahmedullah Aziz

Valley is a useful degree of freedom for non-dissipative electronics since valley current that can flow even in an insulating material does not accompany electronic current. We use dual-gated bilayer graphene in the Hall bar geometry to…

Mesoscale and Nanoscale Physics · Physics 2016-01-20 Yuya Shimazaki , Michihisa Yamamoto , Ivan V. Borzenets , Kenji Watanabe , Takashi Taniguchi , Seigo Tarucha

We demonstrate that unidirectional and backscattering immune propagation of terahertz optical waves can be achieved in a topological valley-Hall waveguide made of graphene nanohole plasmonic crystals. In order to gain deeper physical…

Optics · Physics 2020-06-01 J. W. You , Z. Lan , Q. Bao , N. C. Panoiu

The honeycomb lattice of graphene is a unique two-dimensional (2D) system where the quantum mechanics of electrons is equivalent to that of relativistic Dirac fermions. Novel nanometer-scale behavior in this material, including electronic…

Mesoscale and Nanoscale Physics · Physics 2009-05-29 Yuanbo Zhang , Victor W. Brar , Feng Wang , Caglar Girit , Yossi Yayon , Melissa Panlasigui , Alex Zettl , Michael F. Crommie

This work investigates the feasibility of electrical valley filtering for holes in transition metal dichalcogenides. We look specifically into the scheme that utilizes a potential barrier to produce valley-dependent tunneling rates, and…

Mesoscale and Nanoscale Physics · Physics 2020-05-12 Tzu-Chi Hsieh , Mei-Yin Chou , Yu-Shu Wu

Electrons in two-dimensional hexagonal materials have valley degree of freedom, which can be used to encode and process quantum information. The valley-selective excitations, governed by the circularly polarised light resonant with the…

Mesoscale and Nanoscale Physics · Physics 2021-03-19 M. S. Mrudul , Álvaro Jiménez-Galán , Misha Ivanov , Gopal Dixit

When graphene is deformed in a dynamical manner, a time-dependent potential is induced for the electrons. The potential is antisymmetric with respect to valleys, and some straightforward applications are found for Raman spectroscopy. We…

Mesoscale and Nanoscale Physics · Physics 2014-11-17 Ken-ichi Sasaki , Yasuhiro Tokura , Hideki Gotoh

This is a review on graphene quantum dots and their use as a host for spin qubits. We discuss the advantages but also the challenges to use graphene quantum dots for spin qubits as compared to the more standard materials like GaAs. We start…

Mesoscale and Nanoscale Physics · Physics 2015-05-18 Patrik Recher , Bjoern Trauzettel

Bilayer graphene is a promising platform for electrically controllable qubits in a two-dimensional material. Of particular interest is the ability to encode quantum information in the so-called valley degree of freedom, a two-fold orbital…

Recently, gate-defined Josephson junctions based on magic-angle twisted bilayer graphene (MATBG) have been fabricated. In such a junction, local electrostatic gating can create two superconducting regions connected by an interaction-driven…

Superconductivity · Physics 2023-08-16 Zhong-Chang-Fei Li , Yu-Xuan Deng , Zi-Ting Sun , Jin-Xin Hu , K. T. Law

The valley degree of freedom in many-valley semiconductors provides a new paradigm for storing and processing information in valleytronic and quantum-computing applications. Achieving practical devices require all-electric control of…