Related papers: Electron-nuclei spin dynamics in II-VI semiconduct…
We study the mechanism of dynamical nuclear spin polarization by hyperfine interaction in spin-blocked double quantum dot system. We calculate the hyperfine transition rates and solve the master equations for the nuclear spins.…
Hyperfine coupling of electron spins to nuclear spins is studied for a GaAs-based double quantum dot in the spin blockade regime where the electron conduction is mostly blocked by Pauli effect unless the electron spin state in the double…
We model spin blockade for optically excited electrons and holes in a charged semiconductor quantum dot. We study the case where the quantum dot is initially charged with a single electron and is then filled with an additional, optically…
We report on the spin properties of individual Mn atoms in II-VI semiconductor strain free quantum dots. Strain free Mn-doped CdTe quantum dots are formed by width fluctuations in thin quantum wells lattice matched on a CdTe substrate.…
We theoretically investigate dynamic nuclear spin polarization in a self-assembled quantum dot pumped optically by two laser beams. With the assumption that a noncollinear interaction between the hole spin and nuclear spins leads to nuclear…
Optical control of the spin coherence of quantum well electrons by short laser pulses with circular or linear polarization is studied experimentally and theoretically. For that purpose the coherent electron spin dynamics in a n-doped…
Dynamic nuclear polarization transfers spin polarization from electrons to nuclei. We have achieved this by a new method, simultaneously exciting transitions of electronic and nuclear spins. The efficiency of this technique improves with…
Optical pump-probe techniques are used to generate and measure electron spin polarization in a gallium arsenide epilayer in which the electron spin coherence time exceeds the mode-locked laser repetition period. Resonant spin amplification…
We have studied the time evolution of the electron spin polarization under continuous photoexcitation in remotely n-doped semiconductor quantum wells. The doped region allows us to get the necessary excess of free electrons to form trions.…
Photoluminescence polarization is experimentally studied for samples with (In,Ga)As/GaAs selfassembled quantum dots in transverse magnetic field (Hanle effect) under slow modulation of the excitation light polarization from fractions of Hz…
We have demonstrated experimentally the manipulation of exciton and nuclear spins in a single self-assembled In$_{0.75}$Al$_{0.25}$As/Al$_{0.3}$Ga$_{0.7}$As quantum dot. The oscillation of exciton and nuclear spin polarizations were clearly…
We study the influence of nuclei-induced frequency focusing on the mode locking of spin coherence in quantum dots subjected to a periodic train of optical pulses. In particular, we address the question whether or not nuclei-induced…
The emission of circularly polarized light from a single quantum dot relies on the injection of carriers with well-defined spin polarization. Here we demonstrate single dot electroluminescence (EL) with a circular polarization degree up to…
The spin of a confined electron, when oriented originally in some direction, will lose memory of that orientation after some time. Physical mechanisms leading to this relaxation of spin memory typically involve either coupling of the…
Spin relaxation of electrons doped in InP quantum dots was studied by means of luminescence pump-probe and Hanle measurements. Optical pumping makes spins of doped electrons to be oriented in parallel to the helicity of the circularly…
A hight degree of spin polarization is achieved for a Mn atom localized in a semiconductor quantum dot using quasi-resonant optical excitation at zero magnetic field. Optically created spin polarized carriers generate an energy splitting of…
Dynamic nuclear polarization experiments use microwave irradiation to transfer the larger electron polarization to nuclear spins of interest, and thus enhance the NMR transitions above thermal equilibrium. How the polarization transfer from…
Experimental investigation of nuclear spin effects on the electron spin polarization in singly negatively charged InP quantum dots is reported. Pump-probe photoluminescence measurements of electron spin relaxation in the microsecond…
Optical and electrical control of the nuclear spin system allows enhancing the sensitivity of NMR applications and spin-based information storage and processing. Dynamic nuclear polarization in semiconductors is commonly achieved in the…
We study the exciton spin relaxation in CdTe self-assembled quantum dots by using polarized photoluminescence spectroscopy in magnetic field. The experiments on single CdTe quantum dots and on large quantum dot ensembles show that by…