Improving the fidelity of continuous-variable quantum teleportation by tuning displacement gain

The fidelity of teleportation of continuous quantum variables can be improved by tuning the local displacement gain. We investigate the optimization of the fidelity for the teleportation of Schrodinger cat states, and of coherent states. It is found that the gain corresponding to the maximum fidelity is not equal to one for the two input states in the case of the small squeezing degree of the entanglement resource, while unity displacement gain is the best choice for teleporting arbitrary quantum states in the case of large squeezing.

Improved performance of CdSe/ZnS quantum dot light-emitting diodes through doping with small molecule CBP

The poor film formation of Cd Se/Zn S quantum dots(QDs) during spin-coating makes a substantial impact on the device performance of quantum dot light-emitting diodes(QLEDs). This work proposes a method to improve the morphology of the quantum dot light-emitting layer(EML) by adding small organic molecular 4,4'-Bis(9 H-carbazol-9-yl) biphenyl(CBP) into the layer. Its surface roughness reduces from 6.21 nm to 2.71 nm, which guarantees a good contact between hole transport layer(HTL) and EML. Consequently, the Cd Se/Zn S QDs:CBP based QLED achieves maximum external quantum efficiency(EQE) of 5.86%, and maximum brightness of 10 363 cd/m^(2). It is demonstrated that the additive of small organic molecules could be an effective way to improve the brightness and the efficiency of QLEDs.

Improving the resolution temporal in quantum and classical imaging

The point-spread function of an optical system determines its optical resolution for both spatial and temporal imaging. For spatial imaging, it is given by a Fourier transform of the pupil function of the system. For temporal imaging based on nonlinear optical processes, such as sum-frequency generation or four-wave mixing, the pointspread function is related to the waveform of the pump wave by a nonlinear transformation. We compare the point-spread functions of three temporal imaging schemes： sum-frequency generation, co-propagating four-wave mixing, and counter-propagating four-wave mixing, and demonstrate that the last scheme provides the best temporal resolution. Our results are valid for both quantum and classical temporal imaging.

One-pot synthesis of nuclear targeting carbon dots with high photoluminescence

Carbon dots(CDs) are novel fluorescent nanomaterials with good water solubility, high resistance to photobleaching and low toxicity. While, there are few studies elaborate on the relationship among reaction conditions, properties and applications of CDs. In this study, a series of CDs are synthesized through a one-pot hydrothermal method, and different reaction conditions are carried out to study the influencing factors of CDs properties. As a result, with the increase of temperature and reaction time, the particle size and zeta potential of CDs increased, the maximum emission wavelength red-shifted and the fluorescence quantum yield(QY) improved. Among them, CD3006 has good water solubility and highest QY of 81.4%, which is beneficial for its applications in bioimaging and ion detection. CD3006 is almost nontoxic in cells at a concentration of 500 μg/m L. In addition, the positive charged CD3006 shows nuclear targeting potential because of its combination with DNA through electrostatic interaction in nucleus. The properties of CDs can be greatly enhanced by controlling reaction conditions, and it provides great application prospects.

Orientation dichroism effect of proton scattering on deformed nuclei

Proton-induced scattering of 238U nuclei,with spheroidal deformations at beam energies above 100 MeV,is simulated using an improved quantum molecular dynamics model.The angular distribution of the deflected protons is highly sensitive to the orientation of the symmetrical long axis of the target nuclei with respect to the beam direction.As a result,in reverse kinematic reactions,an orientation dichroism effect is predicted,implying that the absorption rate of the 238U beam by a proton target discerns between the parallel and perpendicular orientations of the deformed 238U nuclei.