On the condition of electric-LO phonon strong-coupling in a parabolic quantum dot, we obtain the eigenenergy of the ground-state and the first-excited state, the eigenfunctions of the ground-state and the first-excite...On the condition of electric-LO phonon strong-coupling in a parabolic quantum dot, we obtain the eigenenergy of the ground-state and the first-excited state, the eigenfunctions of the ground-state and the first-excited state by using variational method of Pekar type. This system in quantum dot may be employed as a two-level quantum system-qubit. When the electron is in the superposition state of the ground- and the first-excited state, we obtain the time evolution of the electron density. The relation of the probability density of electron on the Coulomb binding parameter and the relations of the period of oscillation on the Coulomb binding parameter, the electron-LO-phonon coupling constant and the confinement length are derived.展开更多
The colourless IaA-type gem-quality diamond crystals containing a high concentration of nitrogen(1500–1700 ppm)were successfully prepared by annealing the as-grown Ib-type N-doped diamonds at a high temperature and h...The colourless IaA-type gem-quality diamond crystals containing a high concentration of nitrogen(1500–1700 ppm)were successfully prepared by annealing the as-grown Ib-type N-doped diamonds at a high temperature and high pressure in China-type cubic anvil high-pressure apparatus.Experiments were carried out at pressures of 6.5–7.0 GPa and temperatures from 1900 K to 2100 K.Annealing treatment on high-level N-doped diamond crystals shows that the colour of the diamond crystals is obviously reduced from green to colourless after annealing treatment within 1 h at a higher temperature,which is induced by nitrogen aggregation in the diamond lattice indicated by infrared(IR)spectroscopy.It is further revealed that active energy of the nitrogen atom transforming from the dispersed form to the aggregated form is much lower than that in the standard Ib-type diamond crystals with nitrogen concentration less than 300 ppm.The colourless IaA-type diamond crystal prepared by annealing at 2100 K displays the same properties in IR spectra as the high-quality natural diamonds which are classified into the IaA type.展开更多
基金National Natural Science Foundation of China under Grant No.10347004
文摘On the condition of electric-LO phonon strong-coupling in a parabolic quantum dot, we obtain the eigenenergy of the ground-state and the first-excited state, the eigenfunctions of the ground-state and the first-excited state by using variational method of Pekar type. This system in quantum dot may be employed as a two-level quantum system-qubit. When the electron is in the superposition state of the ground- and the first-excited state, we obtain the time evolution of the electron density. The relation of the probability density of electron on the Coulomb binding parameter and the relations of the period of oscillation on the Coulomb binding parameter, the electron-LO-phonon coupling constant and the confinement length are derived.
基金Supported by the National Natural Science Foundation of China under Grant No 51172089.
文摘The colourless IaA-type gem-quality diamond crystals containing a high concentration of nitrogen(1500–1700 ppm)were successfully prepared by annealing the as-grown Ib-type N-doped diamonds at a high temperature and high pressure in China-type cubic anvil high-pressure apparatus.Experiments were carried out at pressures of 6.5–7.0 GPa and temperatures from 1900 K to 2100 K.Annealing treatment on high-level N-doped diamond crystals shows that the colour of the diamond crystals is obviously reduced from green to colourless after annealing treatment within 1 h at a higher temperature,which is induced by nitrogen aggregation in the diamond lattice indicated by infrared(IR)spectroscopy.It is further revealed that active energy of the nitrogen atom transforming from the dispersed form to the aggregated form is much lower than that in the standard Ib-type diamond crystals with nitrogen concentration less than 300 ppm.The colourless IaA-type diamond crystal prepared by annealing at 2100 K displays the same properties in IR spectra as the high-quality natural diamonds which are classified into the IaA type.
