Related papers: Exciton manifolds in highly ambipolar doped WS2
High resolution laser-based angle-resolved photoemission measurements have been carried out on Bi2Sr2CuO6+d superconductor covering a wide doping range from heavily underdoped to heavily overdoped samples. Two obvious energy scales are…
The presence of two spin-split valleys in monolayer (1L) transition metal dichalcogenide (TMD) semiconductors supports versatile exciton species classified by their spin and valley quantum numbers. While the spin-0 intravalley exciton,…
The low energy band structure and Fermi surface of the newly discovered superconductor, AxFe2Se2 (A=K,Cs), have been studied by angle-resolved photoemission spectroscopy. Compared with iron pnictide superconductors, AxFe2Se2 (A=K,Cs) is the…
We study a mechanism to induce superconductivity in atomically thin semiconductors where excitons mediate an effective attraction between electrons. Our model includes interaction effects beyond the paradigm of phonon-mediated…
Two dimensional materials and their heterostructures constitute a promising platform to study correlated electronic states as well as many body physics of excitons. Here, we present experiments that unite these hitherto separate efforts and…
We compute high-resolution angle-resolved photoemission spectroscopy of the Hubbard model using the unbiased determinant quantum Monte Carlo algorithm, revealing an asymmetry between electron and hole doping. Electron doping exhibits more…
The optical properties of atomically thin semiconductors are dominated by excitons, tightly bound electron-hole pairs, which give rise to particularly rich and remarkable physics. Despite their importance, the microscopic formation…
Semiconductors in all dimensionalities ranging from 0D quantum dots and molecules to 3D bulk crystals support bound electron-hole pair quasiparticles termed as excitons. Over the past two decades, the emergence of a variety of…
Monolayers of ReS2 were grown by a chemical vapor deposition technique on SiO2/Si substrates and investigated at room temperature by using micro-Raman, micro-photoluminescence (PL) and absorbance spectroscopies. The Raman scattering…
We combine linear and non-linear optical spectroscopy at 4K with ab initio calculations to study the electronic bandstructure of MoSe2 monolayers. In 1-photon photoluminescence excitation (PLE) and reflectivity we measure a separation…
Atomically thin semiconductors such as monolayer MoS2 and WS2 exhibit nonlinear exciton-exciton annihilation at notably low excitation densities (below ~10 excitons/um2 in MoS2). Here, we show that the density threshold at which…
Excitons are two-particle correlated bound states that are formed due to Coulomb interaction between single-particle holes and electrons. In the solid-state, cooperative interactions with surrounding quasiparticles can strongly tailor the…
We experimentally demonstrate dressing of the excited exciton states by a continuously tunable Fermi sea of free charge carriers in a monolayer semiconductor. It represents an unusual scenario of two-particle excitations of charged excitons…
We have performed high-resolution angle-resolved photoemission spectroscopy on heavily overdoped KFe_2As_2 (transition temperature (Tc = 3 K). We observed several renormalized bands near the Fermi level with a renormalization factor of 2-4.…
Monolayers of transition-metal dichalcogenides such as WSe2 have become increasingly attractive due to their potential in electrical and optical applications. Because the properties of these 2D systems are known to be affected by their…
Strong electron-phonon interaction which limits electronic mobility of semiconductors can also have significant effects on phonon frequencies. The latter is the key to the use of Raman spectroscopy for nondestructive characterization of…
Excitons in bilayer transition metal dichalcogenides (2L-TMDs) are Coulomb-bound electron/hole pairs that can be viewed as broadly tunable analogs of atomic or molecular systems. Here, we study the properties of 2L-TMD excitons under strong…
A detailed exact-diagonalization study is made for the doping dependence of the single-particle spectral function $A({\bf k},\omega)$ and momentum distribution function $n({\bf k})$ of the two-dimensional $t$$-$$J$ model as a representative…
The optical properties of monolayer transition metal dichalcogenides (TMDC) feature prominent excitonic natures. Here we report an experimental approach toward measuring the exciton binding energy of monolayer WS2 with linear differential…
We discuss the linear and two-photon spectroscopic selection rules for spin-singlet excitons in monolayer transition-metal dichalcogenides. Our microscopic formalism combines a fully $k$-dependent few-orbital band structure with a many-body…