English
Related papers

Related papers: Valley filtering in strain-induced $\alpha$-$\math…

200 papers

Exchange coupling is a key ingredient for spin-based quantum technologies since it can be used to entangle spin qubits and create logical spin qubits. However, the influence of the electronic valley degree of freedom in silicon on exchange…

Mesoscale and Nanoscale Physics · Physics 2018-09-05 J. Salfi , B. Voisin , A. Tankasala , J. Bocquel , M. Usman , M. Y. Simmons , L. C. L. Hollenberg , R. Rahman , S. Rogge

We propose a valley- and spin-filter based on a normal/ferromagnetic/normal molybdenum disulfide (MoS$_2$) junction where the polarizations of the valley and the spin can be inverted by reversing the direction of the exchange field in the…

Mesoscale and Nanoscale Physics · Physics 2015-06-23 Leyla Majidi , Moslem Zare , Reza Asgari

Despite many reports of valley-related phenomena in graphene and its multilayers, current transport experiments cannot probe valley phenomena without the application of external fields. Here we propose a gate-defined valley splitter as a…

Mesoscale and Nanoscale Physics · Physics 2025-02-26 Juan Daniel Torres Luna , Kostas Vilkelis , Antonio L. R. Manesco

Electrons confined in silicon quantum dots exhibit orbital, spin, and valley degrees of freedom. The valley degree of freedom originates from the bulk bandstructure of silicon, which has six degenerate electronic minima. The degeneracy can…

Mesoscale and Nanoscale Physics · Physics 2021-05-05 F. Borjans , X. Zhang , X. Mi , G. Cheng , N. Yao , C. A. C. Jackson , L. F. Edge , J. R. Petta

We propose a simple, yet highly efficient and robust device for producing valley polarized current in graphene. The device comprises of two distinct components; a region of uniform uniaxial strain, adjacent to an out-of-plane magnetic…

Mesoscale and Nanoscale Physics · Physics 2010-08-06 T. Fujita , M. B. A. Jalil , S. G. Tan

Conventional electronics are based invariably on the intrinsic degrees of freedom of an electron, namely, its charge and spin. The exploration of novel electronic degrees of freedom has important implications in both basic quantum physics…

Materials Science · Physics 2013-03-12 Xiao Li , Ting Cao , Qian Niu , Junren Shi , Ji Feng

Valley pseudospin, a new degree of freedom in photonic lattices, provides an intriguing way to manipulate photons and enhance the robustness of optical networks. Here we experimentally demonstrated topological waveguiding, refracting,…

Applied Physics · Physics 2019-08-13 Jingwen Ma , Xiang Xi , Xiankai Sun

One of the intriguing characteristics of honeycomb lattices is the appearance of a pseudo-magnetic field as a result of mechanical deformation. In the case of graphene, the Landau quantization resulting from this pseudo-magnetic field has…

We examine energy spectra of Si quantum dots embedded into Si_{0.75}Ge_{0.25} buffers using atomistic numerical calculations for dimensions relevant to qubit implementations. The valley degeneracy of the lowest orbital state is lifted and…

Mesoscale and Nanoscale Physics · Physics 2009-11-17 S. Srinivasan , G. Klimeck , L. P. Rokhinson

We investigate the effects of a nonuniform uniaxial strain and a triaxial strain on the $\alpha-{\cal T}_3$ lattice. The analytical expressions of the pseudo-Landau levels (pLLs) are derived based on low-energy Hamiltonians, and are…

Mesoscale and Nanoscale Physics · Physics 2022-10-21 Junsong Sun , Tianyu Liu , Yi Du , Huaiming Guo

In a multi-valley electronic band structure, lifting of the valley degeneracy is associated with rotational symmetry breaking in the electronic fluid, and may emerge through spontaneous symmetry breaking order, or through a large response…

Electrical transport in double quantum dots (DQDs) illuminates many interesting features of the dots' carrier states. Recent advances in silicon quantum information technologies have renewed interest in the valley states of electrons…

Mesoscale and Nanoscale Physics · Physics 2017-11-15 Justin K. Perron , Michael J. Gullans , Jacob M. Taylor , M. D. Stewart, , Neil M. Zimmerman

Two dimensional lattices are an important stage for studying many aspects of quantum physics, in particular the topological phases. The valley Hall and anomalous Hall effects are two representative topological phenomena. Here we show that…

Mesoscale and Nanoscale Physics · Physics 2021-07-13 Jiale Yuan , Han Cai , Congjun Wu , Shi-Yao Zhu , Ren-Bao Liu , Da-Wei Wang

Plasma photonic crystals designed in this paper are composed of gas discharge tubes to control the flow of electromagnetic waves. The band structures calculated by the finite element method are consistent with the experimental results in…

Recent progress in the fabrication of quantum dots using silicon opens the prospect of observing the Kondo effect associated with the valley degree of freedom. We compute the dot density of states using an Anderson model with infinite…

Strongly Correlated Electrons · Physics 2015-06-25 Shiue-yuan Shiau , Sucismita Chutia , Robert Joynt

We study the quantum valley Hall effect and related domain wall modes in twisted bilayer graphene at a large commensurate angle. Due to the quantum valley and sub-valley Hall effect, a small deviation from the commensurate angle generates…

Mesoscale and Nanoscale Physics · Physics 2023-09-13 Chiranjit Mondal , Rasoul Ghadimi , Bohm-Jung Yang

The aim of this work is to describe the electronic properties of graphene in a constant magnetic field in the long wavelength approximation with random binary disorder, by solving the Soven equation self-consistently. Density of state…

Mesoscale and Nanoscale Physics · Physics 2015-03-03 Juan Sebastian Ardenghi , Pablo Bechthold , Estela Gonzalez , Paula Jasen , Alfredo Juan

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 have investigated the valley splitting of two-dimensional electrons in high quality Si/Si$_{1-x}$Ge$_x$ heterostructures under tilted magnetic fields. For all the samples in our study, the valley splitting at filling factor $\nu=3$…

Mesoscale and Nanoscale Physics · Physics 2007-05-23 K. Lai , T. M. Lu , W. Pan , D. C. Tsui , S. Lyon , J. Liu , Y. H. Xie , M. Muhlberger , F. Schaffler

A valley filter capable of generating a valley-polarized current is a crucial element in valleytronics, yet its implementation remains challenging. Here, we propose a valley filter made of a graphene bilayer which exhibits a 1D moir\'{e}…

Mesoscale and Nanoscale Physics · Physics 2024-04-19 Kai Shao , Hao Geng , Erfu Liu , Jose L. Lado , Wei Chen , D. Y. Xing