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Related papers: Dynamic Valley Polarization in Moire Quantum Dots

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We show that the combined effect of photon emission and Coulomb interactions may drive an exciton-polariton system towards a dynamical coherent state, even without phonon thermalization or any other relaxation mechanism. Exact…

Mesoscale and Nanoscale Physics · Physics 2013-05-29 Herbert Vinck-Posada , Boris A. Rodriguez , P. S. S. Guimaraes , Alejandro Cabo , Augusto Gonzalez

A theory of an optical vector pulsing soliton of self-induced transparency in an ensemble of semiconductor quantum dots is investigated. It is shown that a distribution of the excitonic ground-state transition dipole moments of the quantum…

Mesoscale and Nanoscale Physics · Physics 2014-08-20 G. T. Adamashvili , M. D. Peikrishvili , R. R. Koplatadze , K. L. Schengelia

We have experimentally studied the pump-probe Kerr rotation dynamics in WSe$_2$ monolayers. This yields a direct measurement of the exciton valley depolarization time $\tau_v$. At T=4K, we find $\tau_v\approx 6$ps, a fast relaxation time…

Mesoscale and Nanoscale Physics · Physics 2014-10-10 C. R. Zhu , K. Zhang , M. Glazov , B. Urbaszek , T. Amand , Z. W. Ji , B. L. Liu , X. Marie

Spontaneous symmetry breaking, arising from the competition of interactions and quantum fluctuations, is fundamental to understanding ordered electronic phases. Although electrically neutral, optical excitations like excitons can interact…

We investigate the optical response of quantum dot molecules coherently driven by polarized laser light. Our description includes the splitting in excitonic levels caused by isotropic and anisotropic exchange interactions. We consider…

Mesoscale and Nanoscale Physics · Physics 2016-11-25 H. S. Borges , A. M. Alcalde , Sergio E. Ulloa

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

Strong-field ionization of atoms by circularly polarized femtosecond laser pulses produces a donut-shaped electron momentum distribution. Within the dipole approximation this distribution is symmetric with respect to the polarization plane.…

The spin dynamics of positively (X$^{+}$) and negatively (X$^{-}$) charged excitons in InP/In$_{0.48}$Ga$_{0.52}$P quantum dots subject to a magnetic field is studied. We find that a characteristic feature of the system under study is the…

Mesoscale and Nanoscale Physics · Physics 2019-12-18 S. V. Nekrasov , I. A. Akimov , Yu. G. Kusrayev , D. R. Yakovlev , M. Bayer

Over the past decade, exciton-polaritons in semiconductor microcavities have attracted a great deal of interest as a driven-dissipative quantum fluid. These systems offer themselves as a versatile platform for performing Hamiltonian…

We study the exciton magnetic polaron (EMP) formation in (Cd,Mn)Se/(Cd,Mg)Se diluted-magnetic-semiconductor quantum wells using time-resolved photoluminescence (PL). The magnetic field and temperature dependencies of this dynamics allow us…

Although energy level repulsion is typically observed in interacting quantum systems, non-Hermitian physics predicts the effect of level attraction, which occurs when significant energy dissipation is present. Here, we show a manifestation…

Mesoscale and Nanoscale Physics · Physics 2024-09-20 Dąbrówka Biegańska , Maciej Pieczarka , Christian Schneider , Sven Höfling , Sebastian Klembt , Marcin Syperek

We describe a mechanism by which an electrical bias voltage applied across a unipolar semiconductor quantum well can drive an exciton or polariton supercurrent. The mechanism depends on the properties of electronic quasiparticles in quantum…

Mesoscale and Nanoscale Physics · Physics 2017-10-17 Ming Xie , David Snoke , A. H. MacDonald

The formation of pulses of surface electromagnetic waves in a metal/dielectric interface is considered in the process of cooperative decay of excitons of quantum dots distributed near a metal surface in a dielectric layer. It is shown that…

Mesoscale and Nanoscale Physics · Physics 2017-03-08 A. V. Shesterikov , M. Yu. Gubin , M. G. Gladush , A. Yu. Leksin , A. V. Prokhorov

The coherent manipulation of spin and pseudospin underlies existing and emerging quantum technologies, including NMR, quantum communication, and quantum computation. Valley polarization, associated with the occupancy of degenerate, but…

Mesoscale and Nanoscale Physics · Physics 2017-02-01 Ziliang Ye , Dezheng Sun , Tony F. Heinz

We consider exciton-polaritons in a honeycomb lattice of micropillars subjected to circularly polarized (${\sigma_\pm}$) incoherent pumps, which are arranged to form two domains in the lattice. We predict that the nonlinear interaction…

Mesoscale and Nanoscale Physics · Physics 2021-07-27 R. Banerjee , S. Mandal , T. C. H. Liew

The orbital, spin and valley degrees of freedom in silicon quantum dots support many modes of spin qubit operation. However, it is generally challenging to obtain information about the energy level spectrum over large ranges of parameter…

Mesoscale and Nanoscale Physics · Physics 2026-04-06 Heun Mo Yoo , Tanner M. Janda , Connor Nasseraddin , Jason R. Petta

A novel spin orientation mechanism - dynamic electron spin polarization has been recently suggested in Phys. Rev. Lett. $\mathbf{125}$, 156801 (2020). It takes place for unpolarized optical excitation in weak magnetic fields of the order of…

Mesoscale and Nanoscale Physics · Physics 2021-09-15 T. S. Shamirzaev , A. V. Shumilin , D. S. Smirnov , J. Rautert , D. R. Yakovlev , M. Bayer

The generation of exciton valley coherence typically requires linearly polarized (LP) light as an external coherent drive, whereas circularly polarized (CP) light fails to induce coherence. Here, we develop a unified,…

Mesoscale and Nanoscale Physics · Physics 2026-03-23 Kang Lan , Xiangji Cai , Zhongxiao Man , Shijie Xie , Ning Hao , Ping Zhang , Jiyong Fu

Two-dimensional transition metal dichalcogenide (TMD) semiconductors provide a unique possibility to access the electronic valley degree of freedom using polarized light, opening the way to valley information transfer between distant…

Valley, as a new degree of freedom for electrons, has drawn considerable attention due to its significant potential for encoding and storing information. Lifting the energy degeneracy to achieve valley polarization is necessary for…

Materials Science · Physics 2020-03-11 Pei Zhaos , Yandong Ma , Hao Wang , Baibiao Huang , Liangzhi Kou , Ying Dai