Related papers: Direct bandgap silicon quantum dots achieved via e…
The direct manipulation of individual atoms in materials using scanning probe microscopy has been a seminal achievement of nanotechnology. Recent advances in imaging resolution and sample stability have made scanning transmission electron…
Scattering of carriers between spatially separated zero dimensional states has been observed in a system of self-assembled In_{0.55}Al_{0.45}As quantum dots. We believe the interdot tunneling is mediated by localized states below the…
We present femtosecond transient transmission (or absorbance) measurements in silicon nanowires in the energy range 1.1-3.5 eV, from below the indirect band-gap to above the direct band-gap. Our pump-probe measurements allow us to give a…
Semiconductor quantum dots in close proximity to superconductors may provoke localized bound states within the superconducting energy gap known as Yu-Shiba-Rusinov (YSR) state, which is a promising candidate for constructing Majorana zero…
Colloidal semiconductor quantum dots are robust emitters implemented in numerous prototype and commercial optoelectronic devices. However, active fluorescence color tuning, achieved so far by electric-field induced Stark effect, has been…
We present a way to manipulate an electron trapped in a layered quantum dot based on near-threshold properties of one-body potentials. We show that potentials with a simple global parameter allows the manipulation of the wave function…
Photon absorption in a semiconductor produces bright excitons that recombine very fast into photons. We here show that in a quantum dot set close to a p-doped reservoir, this absorption can produce a dark duo, i.e., an electron-hole pair…
Intermediate band solar cells (IBSCs) pursue the increase in efficiency by absorbing below-bandgap energy photons while preserving the output voltage. Experimental IBSCs based on quantum dots have already demonstrated that both…
The embedding of tunable quantum emitters in a photonic bandgap structure enables the control of dissipative and dispersive interactions between emitters and their photonic bath. Operation in the transmission band, outside the gap, allows…
We use strain to statically tune the semiconductor band gap of individual InAs quantum dots (QDs) embedded in a GaAs photonic wire featuring very efficient single photon collection efficiency. Thanks to the geometry of the structure, we are…
We perform scanning gate microscopy on individual suspended carbon nanotube quantum dots. The size and position of the quantum dots can be visually identified from the concentric high conductance rings. For the ultra clean devices used in…
We theoretically propose a possibility of realizing high $T_c$ superconductivity having $s\pm$-wave symmetry in the heavily hole-doped infinite layer nickelates La$_{1-x}$Sr$_x$NiO$_2$. We consider situations where the original $P4/mmm$…
We propose a new method to use gapped graphene as barrier to confine electrons in gapless graphene and form a good quantum dot, which can be realized on an oxygen-terminated $SiO_{2}$ substrate partly H-passivated. In particular, we use…
We demonstrate that non-equilibrium electrons in thin nonmagnetic semiconductor layers or quantum dots can be fully spin polarized by means of simultaneous electrical spin injection and extraction. The complete spin polarization is achieved…
Ultra long linear carbon chains of more than 6000 carbon atoms have recently been synthesized within double-walled carbon nanotubes, and they show a promising new route to one--atom--wide semiconductors with a direct band gap. Theoretical…
Epsilon-near-zero (ENZ) materials have been demonstrated to exhibit unique electromagnetic properties. Here we propose the concept of radiative energy bandgap for an ENZ nanoparticle coupled with a quantum emitter (QE). The radiative…
Owing to the Klein tunneling phenomenon, the permanent confinement or localization of electrons within a graphene quantum dot is unattainable. Nonetheless, a constant magnetic field can transiently ensnare an electron within the quantum…
Excitons confined to flat semiconductor quantum dots with elliptical cross section are considered as we study geometrical effects on exciton binding energy, electron-hole separation, and the resulting linear optical properties. We use…
A detailed analysis of the electro-optical response of single as well as coupled semiconductor quantum dots is presented. This is based on a realistic ---i.e., fully tridimensional--- description of Coulomb-correlated few-electron states,…
We present a comprehensive and integrated model-independent ab initio study of the structural, cohesive, electronic, and optical properties of silicon quantum dots of various morphologies and sizes in the framework of all-electron static…