Room-temperature exciton-polaritons with two-dimensional WS2

Flatten, Lucas C.; He, Zhengyu; Coles, David M.; Trichet, A. A. P.; Powell, Alexander W.; Taylor, Robert A.; Warner, Jamie H.; Smith, Jason M.

doi:10.1038/srep33134

Cited by 185 publications

(194 citation statements)

References 40 publications

Supporting

Mentioning

177

Contrasting

Order By: Relevance

“…The corresponding photonic states are not coupled to the exciton at high k, and therefore do not contribute to the physics of the problem. Therefore, we introduce a saturation of the photonic dispersion and of the photonic SOC at a frequency of 10 15 Hz (≈ 626 meV above the cavity mode), to make the numerical simulations feasible with a time step of 10 −16 s. The spatial grid size was 2048 2 points.…”

Section: Numerical Simulationsmentioning

confidence: 99%

Optical valley Hall effect based on transitional metal dichalcogenide cavity polaritons

2017

View full text Add to dashboard Cite

We calculate the dispersion of spinor exciton-polaritons in a planar microcavity with its active region containing a single Transitional Metal Dichalcogenide (TMD) monolayer, taking into account excitonic and photonic spin-orbit coupling. We consider the radial propagation of polaritons in presence of disorder. We show that the reduction of the disorder scattering induced by the formation of polariton states allows to observe an optical Valley Hall effect, namely the coherent precession of the locked valley and polarization pseudospins leading to the formation of spatial valley-polarized domains.2D materials represent an enormous emergent field of research in modern Physics [1][2][3]. TMD monolayers, due to their chemical structure, exhibit a bandgap at optical frequencies with a strong excitonic resonance [4][5][6]. The oscillator strength of these excitons is so large that it is possible to observe strong light-matter coupling regime with TMD monolayers [7,8] up to room temperature [9][10][11]. Because of the honeycomb lattice and the absence of the inversion symmetry, the band structure of TMDs is characterized by 2 valleys with opposite Berry curvature at the corners of the Brillouin zone (usually marked K and K ). This leads to particular selection rules for optical emission and absorption: each of the two valleys is definitely associated with its own circular polarization of emitted and absorbed photons, which allows valley pumping and detection using circularly polarized light. Another consequence is a new kind of Hall effect: the Valley Hall effect [12]. In doped samples, electrons from the two valleys, accelerated by an electric field, undergo opposite lateral drift (anomalous velocity) because of the opposite Berry curvature [13,14]. Scattering and re-acceleration of carriers lead to an overall valley current perpendicular to the main electrical current.The spin-orbit coupling (SOC) in these materials is also particularly strong. It suppresses spin relaxation and leads to the coupling of spin and valley degrees of freedom [15]. This has inspired the development of valleytronics [16]: an analogue of spintronics, where the information is stored in the valley degree of freedom of carriers, which can offer a better protection against relaxation [17][18][19]. Its optical counterpart, the optovalleytronics, is based on the optical pumping, either resonant or non-resonant [15,[20][21][22], with circular or linear polarization, which allows to selectively populate either a single valley or a coherent superposition of valleys. However, the explicit accounting for the coupling to light leads to a coupling between circularly polarized excitons, which can also be seen as the consequence of the long-range electron-hole Coulomb exchange interaction [23,24]. The two spins, and therefore valleys, form a doublet of excitons coupled to linearly polarized TE and TM light modes. In the well-mastered GaAs quantum wells, this polarization splitting scales quadratically versus the wave vector k, and, combined with random sca...

show abstract

Section: Numerical Simulationsmentioning

confidence: 99%

Optical valley Hall effect based on transitional metal dichalcogenide cavity polaritons

2017

View full text Add to dashboard Cite

show abstract

“…For example, TMD planar waveguides could serve as F‐P microcavities due to their capability of confining photons within the waveguide . In addition, F‐P cavities based on metal mirrors were also used to create EPs in TMDs . In nearly all cases, the strong coupling between cavity photons and excitons is confirmed by the measurements of Rabi splitting energy Ω R , which is typically in the order of tens to hundreds of meV.…”

Section: Far‐field Spectroscopy Studies Of Eps In Tmdsmentioning

confidence: 99%

Recent Progress on Exciton Polaritons in Layered Transition‐Metal Dichalcogenides

Fei

2019

Advanced Optical Materials

View full text Add to dashboard Cite

Exciton polaritons (EPs) are half‐light, half‐matter quasiparticles formed due to the coupling between photons and excitons in semiconductors. Their uniqueness lies at the strong light–matter interactions and long‐distance transport, thus promising for many novel applications in photonics, information, and quantum technologies. Recently, EPs in group‐VI transition‐metal dichalcogenides (TMDs) have attracted a lot of research interest due to their room‐temperature stability, long‐distance propagation, and controllability through electric gating, valley‐selective optical pumping, and precise thickness control. In this progress report, recent studies of EPs in TMDs are reviewed, highlighting their key properties and functionalities, and then discussing the potential directions for future research.

show abstract

“…In 2016, Flatten et al. demonstrated strong coupling regime at room temperature with WS 2 monolayers in a chip‐based planar–planar open‐access microcavity in 2016, showing a vacuum Rabi splitting of 70 meV.…”

Section: Exciton‐polaritons In Open‐access Microcavitiesmentioning

confidence: 99%

Tunable Open‐Access Microcavities for Solid‐State Quantum Photonics and Polaritonics

Cai

et al. 2019

Adv Quantum Tech

View full text Add to dashboard Cite

Optical microcavities are powerful platforms widely applied in quantum information and integrated photonic circuits, among which the open‐access microcavity is a newly emerging cavity structure consisting of a micro‐sized concave mirror and a planar mirror controlled individually by groups of nanopositioners, whilst light emitters can be grown or transferred at the antinode of the cavity optical modes. Compared with monolithic microcavities, the open‐access microcavity enables the simultaneous realization of small mode volume, large‐range tunability, flexible structural engineering, and easiness for integration with external emitters, exhibiting extensive applications in the fields of solid‐state quantum photonics and polaritonics over the last decade. This review first introduces the basic theory and the construction methods of open‐access microcavities, followed by the recent advances of their applications in exciton‐polaritons, photon condensates, quantum light sources, and nanoparticle sensing.

show abstract

Room-temperature exciton-polaritons with two-dimensional WS2

Cited by 185 publications

References 40 publications

Optical valley Hall effect based on transitional metal dichalcogenide cavity polaritons

Optical valley Hall effect based on transitional metal dichalcogenide cavity polaritons

Recent Progress on Exciton Polaritons in Layered Transition‐Metal Dichalcogenides

Tunable Open‐Access Microcavities for Solid‐State Quantum Photonics and Polaritonics

Contact Info

Product

Resources

About