English
Related papers

Related papers: Spin-Valley Protected Kramers Pair in Bilayer Grap…

200 papers

Bilayer graphene bears an eight-fold degeneracy due to spin, valley and layer symmetry, allowing for a wealth of broken symmetry states induced by magnetic or electric fields, by strain, or even spontaneously by interaction. We study the…

Mesoscale and Nanoscale Physics · Physics 2012-02-15 F. Freitag , J. Trbovic , M. Weiss , C. Schönenberger

We investigate topological phases of bilayer graphene subject to antiferromagnetic exchange field, interlayer bias, and irradiated by light. We discover that at finite bias and light intensity the system transitions into a previously…

Mesoscale and Nanoscale Physics · Physics 2020-04-29 Xuechao Zhai , Yaroslav M. Blanter

Two monolayers of graphene twisted by a small `magic' angle exhibit nearly flat bands leading to correlated electronic states and superconductivity, whose precise nature including possible broken symmetries, remain under debate. Here we…

Strongly Correlated Electrons · Physics 2019-12-13 Jong Yeon Lee , Eslam Khalaf , Shang Liu , Xiaomeng Liu , Zeyu Hao , Philip Kim , Ashvin Vishwanath

Moir\'e superlattices formed from transition metal dichalcogenides (TMDs) have been shown to support a variety of quantum electronic phases that are highly tunable using applied electromagnetic fields. While the valley character of the…

We present a study on the lifting of degeneracy of the size-quantized energy levels in an electrostatically defined quantum point contact in bilayer graphene by the application of in-plane magnetic fields. We observe a Zeeman spin splitting…

Mesoscale and Nanoscale Physics · Physics 2022-02-03 Vanessa Gall , Rainer Kraft , Igor V. Gornyi , Romain Danneau

We report on the investigation of proximity-induced spin-orbit coupling (SOC) in a heterostructure of bilayer graphene (BLG) and tungsten diselenide (WSe$_2$). A BLG quantum dot (QD) in the few-particle regime acts as a sensitive probe for…

The development of valleytronics demands long-range electronic transport with preserved valley index, a degree of freedom similar to electron spin. A promising structure for this end is a topological one-dimensional (1D) channel formed in…

Mesoscale and Nanoscale Physics · Physics 2019-01-25 E. Mania , A. R. Cadore , T. Taniguchi , K. Watanabe , L. C. Campos

Electron-electron interactions play an important role in graphene and related systems and can induce exotic quantum states, especially in a stacked bilayer with a small twist angle. For bilayer graphene where the two layers are twisted by a…

The coherent dynamics of a quantum mechanical two-level system passing through an anti-crossing of two energy levels can give rise to Landau-Zener-St\"uckelberg-Majorana (LZSM) interference. LZSM interference spectroscopy has proven to be a…

The flat bands in bilayer graphene(BLG) are sensitive to electric fields E\bot directed between the layers, and magnify the electron-electron interaction effects, thus making BLG an attractive platform for new two-dimensional (2D) electron…

Mesoscale and Nanoscale Physics · Physics 2012-03-23 J. Velasco , L. Jing , W. Bao , Y. Lee , P. Kratz , V. Aji , M. Bockrath , C. N. Lau , C. Varma , R. Stillwell , D. Smirnov , Fan Zhang , J. Jung , A. H. MacDonald

The existence of inequivalent valleys K and K' in the momentum space of two-dimensional hexagonal lattices provides a new electronic degree of freedom, the manipulation of which can potentially lead to new types of electronics, in analogy…

Mesoscale and Nanoscale Physics · Physics 2016-11-03 J. Li , K. Wang , K. J. McFaul , Z. Zern , Y. F. Ren , K. Watanabe , T. Taniguchi , Z. H. Qiao , J. Zhu

In a Bernal-stacked graphene bilayer, an electronic state in Landau level $% N=0$ is described by its guiding-center index $X$ (in the Landau gauge) and by its valley, spin, and orbital indices $\xi =\pm K,\sigma =\pm 1,$ and $% n=0,1.$…

Mesoscale and Nanoscale Physics · Physics 2014-01-08 J. Lambert , R. Côté

Two dimensional moir\'e systems have recently emerged as a platform in which the interplay between topology and strong correlations of electrons play out in non-trivial ways. Among these systems, twisted double bilayer graphene (TDBG) is of…

Mesoscale and Nanoscale Physics · Physics 2023-10-03 Debasmita Giri , Dibya Kanti Mukherjee , H. A. Fertig , Arijit Kundu

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

Electronic spins in Silicon (Si) are rising contenders for qubits -- the logical unit of quantum computation-- owing to its outstanding spin coherence properties and compatibility to standard electronics. A remarkable limitation for spin…

Mesoscale and Nanoscale Physics · Physics 2015-06-15 Lijun Zhang , Jun-Wei Luo , A. L. Saraiva , Belita Koiller , Alex Zunger

We propose a general and tunable platform to realize high-density arrays of quantum spin-valley Hall kink (QSVHK) states with spin-valley-momentum locking based on a two-dimensional hexagonal topological insulator. Through the analysis of…

Mesoscale and Nanoscale Physics · Physics 2021-09-10 Tong Zhou , Shuguang Cheng , Michael Schleenvoigt , Peter Schuffelgen , Hua Jiang , Zhongqin Yang , Igor Zutic

Since the lattices of ABA-stacked graphene multilayers with an even number of layers, as well as that of monolayer graphene, satisfy spatial-inversion symmetry, their electronic bands must be spin degenerate in the presence of…

Mesoscale and Nanoscale Physics · Physics 2013-05-29 Edward McCann , Mikito Koshino

The tuneability and control of quantum nanostructures in two-dimensional materials offer promising perspectives for their use in future electronics. It is hence necessary to analyze quantum transport in such nanostructures. Material…

Mesoscale and Nanoscale Physics · Physics 2022-11-01 Angelika Knothe , Leonid I. Glazman , Vladimir I. Fal'ko

Twisted double bilayer graphene (tDBG) comprises two Bernal-stacked bilayer graphene sheets with a twist between them. Gate voltages applied to top and back gates of a tDBG device tune both the flatness and topology of the electronic bands,…

We show nonlinear transport experiments on clean, suspended bilayer graphene that reveal a gap in the density of states. Looking at the evolution of the gap in magnetic fields of different orientation, we find that the groundstate is a…

Mesoscale and Nanoscale Physics · Physics 2013-04-16 Frank Freitag , Markus Weiss , Romain Maurand , Jelena Trbovic , Christian Schönenberger