Balocchi, A - www.sciencegate.ch

2021-04-06: Purcell effect on CdSe/ZnSe quantum dots em bedded in pillar microcavities

Robin, I.C.;André, Régis;Balocchi, A.;Carayon, S.;Gérard, J.M.;Kheng, K.;Dang, Le Si;Mariette, H.;Moehl, Sebastien;TINJOD, Frank

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2021-03-30: Electrically tunable dynamic nuclear spin polarization in GaAs quantum dots at zero magnetic field

Manca, M;Wang, G;Kuroda, T;Shree, S;Balocchi, A;Renucci, P;Marie, X;Durnev, MV;Glazov, MM;Sakoda, K;Mano, T;Amand, T;Urbaszek, B;,

In III-V semiconductor nano-structures, the electron and nuclear spin dynamics are strongly coupled. Both spin systems can be controlled optically. The nuclear spin dynamics are widely studied, but little is known about the initialization mechanisms....

2021-03-30: Electron spin dephasing and optical pumping of nuclear spins in GaN

Wang, G;Zhu, CR;Liu, BL;Ye, H;Balocchi, A;Amand, T;Urbaszek, B;Yang, H;Marie, X;,

We have measured the donor-bound electron spin dynamics in cubic GaN by time-resolved Kerr rotation experiments. The ensemble electron spin dephasing time in this quantum-dot-like system characterized by a Bohr radius of 2.5 nm is of the order of 1.5...

2021-03-30: Exciton dynamics in WSe2 bilayers

Wang, G;Marie, X;Bouet, L;Vidal, M;Balocchi, A;Amand, T;Lagarde, D;Urbaszek, B;,

We investigate exciton dynamics in WSe bilayers in time-resolved photoluminescence (PL) spectroscopy. Fast PL emission times are recorded for both the direct exciton with τ ≲3 ps and the indirect optical transition with τ ≈25 ps. For temperatures bet...

2021-03-30: Exciton radiative lifetime in transition metal dichalcogenide monolayers

Robert, C;Lagarde, D;Cadiz, F;Wang, G;Lassagne, B;Amand, T;Balocchi, A;Renucci, P;Tongay, S;Urbaszek, B;Marie, X;,

We have investigated the exciton dynamics in transition metal dichalcogenide monolayers using time-resolved photoluminescence experiments performed with optimized time resolution. For MoSe2 monolayer, we measure τrad0=1.8±0.2ps at T=7K that we interp...

2021-03-30: Exciton states in monolayer MoSe2: Impact on interband transitions

Wang, G;Gerber, IC;Bouet, L;Lagarde, D;Balocchi, A;Vidal, M;Amand, T;Marie, X;Urbaszek, B;,

We combine linear and nonlinear optical spectroscopy at 4 K with ab initio calculations to study the electronic bandstructure of MoSe monolayers. In one-photon photoluminescence excitation (PLE) and reflectivity we measure a separation between the A-...

2021-03-30: Valley dynamics probed through charged and neutral exciton emission in monolayer WSe2

Wang, G;Bouet, L;Lagarde, D;Vidal, M;Balocchi, A;Amand, T;Marie, X;Urbaszek, B;,

Optical interband transitions in monolayer transition metal dichalcogenides such as WSe2 and MoS2 are governed by chiral selection rules. This allows efficient optical initialization of an electron in a specific K valley in momentum space. Here we pr...

2021-03-30: Magnetic field effect on electron spin dynamics in (110) GaAs quantum wells

Wang, G;Balocchi, A;Poshakinskiy, AV;Zhu, CR;Tarasenko, SA;Amand, T;Liu, BL;Marie, X;,

We study the electron spin relaxation in both symmetric and asymmetric GaAs/AlGaAs quantum wells (QWs) grown on (110) substrates in an external magnetic field B applied along the QW normal. The spin polarization is induced by circularly polarized lig...

2021-03-30: Growth direction dependence of the electron spin dynamics in {111} GaAs quantum wells

Ye, HQ;Wang, G;Liu, BL;Shi, ZW;Wang, WX;Fontaine, C;Balocchi, A;Amand, T;Lagarde, D;Renucci, P;Marie, X;,

The electron spin dynamics is studied by time-resolved Kerr rotation in GaAs/AlGaAs quantum wells embedded in NIP structures grown on (111)A or (111)B-oriented substrates. In both cases the spin lifetimes are significantly increased by applying an ex...

2021-03-30: Giant Enhancement of the Optical Second-Harmonic Emission of WSe2 Monolayers by Laser Excitation at Exciton Resonances

Wang, G;Marie, X;Gerber, I;Amand, T;Lagarde, D;Bouet, L;Vidal, M;Balocchi, A;Urbaszek, B;,

We show that the light-matter interaction in monolayer WSe2 is strongly enhanced when the incoming electromagnetic wave is in resonance with the energy of the exciton states of strongly Coulomb bound electron-hole pairs below the electronic band gap....