VLADIMIROVA , Maria

Indirect excitons (IXs) offer an opportunity to explore dipolar bosonic fluids in semiconductors. Indeed, IXs are quasiparticles hosted by quantum heterostructures, e.g. quantum wells (QWs). Such IXs are Coulomb-bound pairs consisting of an electron and a hole individually confined at the two opposite QW interfaces. Main properties of IX...

The Mott transition from a dipolar excitonic liquid to an electron-hole plasma is demonstrated in a wide GaN/(Al,Ga)N quantum well at $T=7$K by means of spatially-resolved magneto-photoluminescence spectroscopy. Increasing optical excitation density we drive the system from the excitonic state, characterized by a diamagnetic behavior and thus a...

Dipolar, or indirect excitons (IXs) offer a rich playground for both design of novel optoelectronic devices and fundamental many-body physics. Wide GaN/(AlGa)N quantum wells host a new and promising realization of such excitons. Indeed, compared to their counterparts in GaAs-based heterostructures, IXs in nitrides possess two key advantages....

Dipolar, or indirect excitons (IXs) offer a rich playground for both design of novel optoelectronic devices and fundamental many-body physics. Wide GaN/(AlGa)N quantum wells host a new and promising realization of such excitons. Indeed, compared to their counterparts in GaAs-based heterostructures, IXs in nitrides possess two key advantages....

Due to giant built-in electric fields excitons in wide GaN/(Al,Ga)N quantum wells (QWs) are spatially indirect iven in the abscence of any external electric bias and posess microsecond lifetimes, large dipole moment in growth direction, and tens of microns diffusion lengths [Fedichkin2016]. This make them potentially interesting for excitonic...

The Mott transition from a dipolar excitonic liquid to an electron-hole plasma is demonstrated in a wide GaN/(Al,Ga)N quantum well at $T=7$K by means of spatially-resolved magneto-photoluminescence spectroscopy. Increasing optical excitation density we drive the system from the excitonic state, characterized by a diamagnetic behavior and thus a...

A giant built-in electric field in the growth direction makes excitons in wide GaN/(Al, Ga)N quantum wells spatially indirect even in the absence of any external bias. Significant densities of indirect excitons can accumulate in electrostatic traps imprinted in the quantum well plane by a thin metal layer deposited on top of the...

Light emission in polar group-III nitride quantum wells (QWs) optically pumped at densities significantly below the lasing threshold is usually interpreted in terms of excitons. Whereas thin GaN QWs with fast radiative lifetimes are employed in light-emitting devices, the excitons in thick QWs (typ. 7nm) are characterized by a non-zero dipole...

In group-III nitride quantum wells, indirect excitons (IXs) are naturally formed because the electron-hole pair is separated along the growth (0001) axis by strong internal electric fields. These IXs therefore exhibit strong permanent dipole moments and extremely long radiative lifetimes (> 10µs). Previous extensive studies of IXs in...

Dipolar excitons offer a rich playground for both design of novel optoelectronic devices and fundamental many-body physics. Wide GaN/(AlGa)N quantum wells host a new and promising realization of dipolar excitons. We demonstrate the in-plane confinement and cooling of these excitons, when trapped in the electrostatic potential created by...

Light emission in polar group-III nitride quantum wells optically pumped at densities significantly below the lasing threshold is usually interpreted in terms of excitons. Such excitons are characterized by a non-zero dipole moment and long radiative lifetimes, because their constituent electron and hole are spatially separated by the built-in...

Excitons in nitride quantum wells (QWs) are naturally indirect due to the strong internal electric field: electron and hole within such excitons are spatially separated, leading to strong dipole moments and long radiative lifetimes. The physics of indirect excitons (IXs) has been extensively studied in GaAs-based heterostructures: they can...

Excitons in wide nitride Quantum Wells (QWs) are naturally indirect due to the strong internal electric field: within such excitons the electron and the hole are spatially separated, resulting in strong dipole moments and long radiative lifetimes. These properties offer the possibility to explore the collective exitonic phases with complex...

We investigate the transport of dipolar indirect excitons along the growth plane of polar (Al,Ga)N/GaN quantum well structures by means of spatially and time-resolved photoluminescence spectroscopy. The transport in these strongly disordered quantum wells is activated by dipole-dipole repulsion. The latter induces an emission blue shift that...

We report on spatially- and time-resolved emission measurements and observation of transport of indirect excitons in ZnO/MgZnO wide single quantum wells.