English
Related papers

Related papers: Valley polarization in MoS2 monolayers by optical …

200 papers

Electronic and spintronic devices rely on the fact that free charge carriers in solids carry electric charge and spin, respectively. There are, however, other properties of charge carriers that might be exploited in new families of devices.…

Mesoscale and Nanoscale Physics · Physics 2015-06-05 Kin Fai Mak , Keliang He , Jie Shan , Tony F. Heinz

Modern electronic devices heavily rely on the accurate control of charge and spin of electrons. The emergence of controllable valley degree of freedom brings new possibilities and presents a promising prospect towards valleytronics.…

We report polarization resolved photoluminescence from monolayer MoS2, a two-dimensional, non-centrosymmetric crystal with direct energy gaps at two different valleys in momentum space. The inherent chiral optical selectivity allows…

Materials Science · Physics 2012-08-10 G. Sallen , L. Bouet , X. Marie , G. Wang , C. R. Zhu , W. P. Han , Y. Lu , P. H. Tan , T. Amand , B. L. Liu , B. Urbaszek

A photoinduced current of a layered MoS2-based transistor is studied from first-principles. Under the illumination of circular polarized light, a valley-polarized current is generated, which can be tuned by the gate voltage. For monolayer…

Mesoscale and Nanoscale Physics · Physics 2017-01-09 Yunjin Yu , Yanfeng Zhou , Langhui Wan , Bin Wang , Fuming Xu , Yadong Wei , Jian Wang

We investigate with polarized microphotoluminescence the optical pumping of the valley degree of freedom in charge-tunable MoS2 monolayers encapsulated with hexagonal boron nitride at cryogenic temperatures. We report a large steady state…

Mesoscale and Nanoscale Physics · Physics 2021-10-15 Sangjun Park , Steve Arscott , Takashi Taniguchi , Kenji Watanabe , Fausto Sirotti , Fabian Cadiz

Monolayer $MoS_2$ is a typical valleytronic material with valley-spin locked valence bands. We numerically investigate the valley-spin polarized current in monolayer $\rm MoS_2$ via adiabatic electron pumping. By introducing an exchange…

Mesoscale and Nanoscale Physics · Physics 2023-01-30 Kai-Tong Wang , Hui Wang , Fuming Xu , Yunjin Yu , Yadong Wei

We investigate the valley related carrier dynamics in monolayer MoS2 using helicity resolved non-degenerate ultrafast pump-probe spectroscopy at the vicinity of the high-symmetry K point under the temperature down to 78 K. Monolayer MoS2…

Optics · Physics 2014-05-08 Qinsheng Wang , Shaofeng Ge , Xiao Li , Jun Qiu , Yanxin Ji , Ji Feng , Dong Sun

We have investigated the steady-sate valley polarization and valley coherence of encapsulated MoS2 monolayer as a function of the temperature and the power density with a continuous wave laser excitation. Both valley polarization and…

Materials Science · Physics 2021-11-01 Fabian Cadiz , Stefan Gerl , Takashi Taniguchi , Kenji Watanabe

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

We theoretically demonstrate that 100\% valley-polarized transport in monolayers of MoS$_{2}$ and other group-VI dichalcogenides can be obtained using off-resonant circularly polarized light. By tuning the intensity of the off-resonant…

Mesoscale and Nanoscale Physics · Physics 2015-04-21 M. Tahir , A. Manchon , U. Schwingenschlogl

We induce control over valley polarization with a polarization-shaped mid-infrared light field. The polarization state of the trefoil-shaped pump fields is measured by high harmonic spectroscopy, which we also use to confirm strong field…

The valley degree of freedom of electrons in materials promises routes toward energy-efficient information storage with enticing prospects towards quantum information processing. Current challenges in utilizing valley polarization are…

Single layers of MoS2 and MoSe2 were optically pumped with circularly polarized light and an appreciable polarization was initialized as the pump energy was varied. The circular polarization of the emitted photoluminescence was monitored as…

Materials Science · Physics 2016-02-02 George Kioseoglou , Aubrey T. Hanbicki , Marc Currie , Adam L. Friedman , Berend T. Jonker

In this Letter, a tunable valley polarization is investigated for honeycomb systems with broken inversion symmetry such as transition-metal dichalcogenide MX2 (M = Mo, W; X = S, Se) monolayers through elliptical pumping. As compared to…

Mesoscale and Nanoscale Physics · Physics 2014-11-26 Zhigang Song , Ruge Quhe , Yan Li , Ji Feng , Jing Lu , Jinbo Yang

In monolayer MoS2 optical transitions across the direct bandgap are governed by chiral selection rules, allowing optical valley initialization. In time resolved photoluminescence (PL) experiments we find that both the polarization and…

Mesoscale and Nanoscale Physics · Physics 2014-02-04 D. Lagarde , L. Bouet , X. Marie , C. R. Zhu , B. L. Liu , T. Amand , P. H. Tan , B. Urbaszek

A monolayer of $MoS_{2}$ has a non-centrosymmetric crystal structure, with spin polarized bands. It is a two valley semiconductor with direct gap falling in the visible range of the electromagnetic spectrum. Its optical properties are of…

Mesoscale and Nanoscale Physics · Physics 2023-06-09 Zhou Li , J. P. Carbotte

Opto-spintronics is an emerging field where ultra-thin magnetic-semiconductors having high spin-valley coupling play an important role. Here, we demonstrate substitutional vanadium (V) doping in MoS$_2$ lattice in different extent, leading…

Manipulating spin polarization of electrons in nonmagnetic semiconductors by means of electric fields or optical fields is an essential theme of the conceptual nonmagnetic semiconductor-based spintronics. Here we experimentally demonstrate…

Mesoscale and Nanoscale Physics · Physics 2016-03-31 Xie Lu , Xiaodong Cui

We have investigated the valley degeneracy of MoS2 multilayers and its effect on thermoelectric properties. By modulating the layer thickness and external electric field, the hole valleys at {\Gamma} and K points in the highest energy…

Materials Science · Physics 2016-02-03 Jisook Hong , Changhoon Lee , Jin-Seong Park , Ji Hoon Shim

Abstract The valley degree of freedom in two-dimensional materials provides an opportunity to extend the functionalities of valleytronics devices. Very short valley lifetimes demand the ultrafast control of valley pseudospin. Here, we…

‹ Prev 1 2 3 10 Next ›