Decoherence-immune generation of highly entangled states for two atoms

This paper proposes a decoherence-immune scheme for generating highly entangled states for two atoms trapped in a cavity. The scheme is based on two resonant atom-cavity interactions. Conditional upon the detection of no photon, the two atoms may exchange an excitation via the first resonant interaction, which leads to entanglement. Due to the loss of the excitation, the two atoms are in a mixed entangled state. With the help of an auxiliary ground state not coupled to the cavity mode, the state related to the excitation loss is eliminated by the detection of a photon resulting from the second resonant interaction. Thus, the fidelity of entanglement is almost not affected by the decoherence.

Preparation of Macroscopic Quantum-Interference States for a Collection of Trapped Ions Via a Single Geometric Operation

我们由单个几何阶段操作为许多套住的离子为宏观的量干扰状态的产生描述一个计划。在计划，震动的模式处于某个扎根的电子状态与与离子的数字成正比的半径沿着一个圆被代替。在一给定的相互作用时间，震动的模式回到原来的状态，并且离子的系统获得与圆的区域成正比的一个几何阶段，从一个协调状态演变到二个协调状态的重叠。离子不在操作期间经历电子转变。利用几何操作的固有的差错容忍的特征，我们的计划对 decoherence 是柔韧的。

Photocatalysis Activity and Physicochemical Structure of Titanium Dioxide Co-doped with N and B

Titanium dioxide co-doped with N and B was prepared by sol-gel method. The photocatalytic activity was evaluated by the photodegradation of methylene blue under visible light. Its physicochemical properties were characterized by means of UV-Vis DRS, XRD, PT-IR, and XPS. The results indicated that N-B-TiO2 has good activity to the photodegradation of MB. Its decolourizing rate of methylene blue solution goes up to 98.4% under the visible light irradiation with 5 h. The doping nitrogen forms N-Ti-O and boron primarily existing in oxide appears in the N-B-TiO2 sample. They response for visible light of TiOa was also exploited.

Robust generation of qutrit entanglement via adiabatic passage of dark states

We propose a scheme for the deterministic generation of qutrit entanglement for two atoms trapped in an optical cavity. Taking advantage of the adiabatic passage, the operation is immune to atomic spontaneous emission as the atomic excited states are never populated; under certain conditions, the probability that the cavity is excited is negligible. We also study the influences of the dissipation due to the atomic spontaneous emission and cavity decay.

Generation of any superposition of coherent states along a straight line via resonant atom-cavity interaction

This paper proposes a scheme for generating arbitrary superpositions of several coherent states along a straight line for a cavity mode. In the scheme, several atoms are sent through a cavity initially in a strong coherent state. The superposition of several coherent states with desired coefficients may be generated if each atom is detected in the excited state after it exits the cavity. The scheme is based on resonant atom-cavity interaction and no classical field is required during and after the atom cavity interaction. Thus, the scheme is very simple and the interaction time is very short, which is important in view of decoherence.

Researches on the Treatment of Phosphorous Wastewater with Oyster Shells

Based on the analysis of adsorptive features of oyster shells,the researches on the treatment of phosphorous wastewater with oyster shells and the effect of temperature on phosphorus removal were carried out.XRD was used to characterize the crystalline phases,and the main component of oyster shells was shown to be CaCO3.When the pretreatment temperature reached 800 ℃,some CaCO3 decomposed into CaO.As the temperature was further raised,CaO increased gradually.Via SEM testing,the oyster shell was a kind of natural porous materials.The pore wall partially collapsed from 550 to 900 ℃.No obvious porous structure was found at 900 ℃.However,without preheating,the oyster shell phosphorous removal material can not adsorb the phosphorus.Pretreatment made calcium activate,thus greatly increasing the absorption of phosphorus.

Researches on the Removal of Pb(Ⅱ) by Hydrothermally Modified Oyster Shells

A novel wastewater purification material was prepared by a hydrothermal method. It was mainly made from oyster shells with the merits of long service time, large surface area, high lead removal efficiency and excellent recyclable properties. The technological conditions were decided respectively based on the lead removal efficiencies. At pH = 5 and 30 ℃, for the wastewater with the initial concentration of Pb2＋ to be 5 mg/L, adsorption time 24 h, and 1 mg to 40 mL of mass ratio between adsorbent and Pb2＋, the maximum adsorption capacity can reach 0.19 mg/g. The lead removal material prepared by hydrothermal method has excellent recycle performance. The equilibrium adsorption capacity can get to 9.71 mg/g and the average Pb2＋ removal rate is as high as 66.39%. After reusing for 60 times, the SEM observation shows that the hydrates of reticular formation is formed after hydrothermal modification, which provides a good attachment position for Pb2＋, indicating the physical adsorption is dominant.

Syntheses, Structures and Photoluminescence of Two New Layered Lanthanide Coordination Polymers with Thiophenedicarboxylic Acid and 1,10-Phenanthroline

Two isostructural layered coordination polymers constructed from mixed ligands, [Ln2（tdc）3（phen）2（H2O）2] （Ln = Sm 1, Eu 2, H2tdc = thiophene-2,5-dicarboxylic acid, phen = 1,10-phenanthroline）, have been hydrothermally synthesized and characterized by elemental analysis, IR and single-crystal X-ray diffraction. Crystal data for 1： triclinic, space group P1 with a = 10.546（2）, b = 11.201（2）, c = 18.644（4）A, α = 106.69（3）, β = 91.27（3）, γ = 94.43（3）°, Dc = 1.909 g·cm-3, F（000） = 1180, μ = 2.992 mm^-1, Z = 2, the final R = 0.0300 and wR = 0.0656 for 6968 observed reflections with I 〉 2σ（I）. And those for 2： triclinic, space group P1^- with a = 10.557（2）, b = 11.159（2）, c = 18.588（2） A, α = 106.945（6）, β = 91.255（6）, γ = 94.359（6）°, Dc = 1.927 g·cm^-3, F（000） = 1184, μ = 3.204 mm^-1, Z = 2, the final R = 0.0221 and wR = 0.0459 for 6328 observed reflections with I 〉 2σ（I）. The title complexes show a two-dimensional （2D） square grid structure constructed from paddle-wheel-like [Ln2（CO2）4] dimers and tdc ligands. The 2D layers were further assembled into a 3D supramolecular assembly via O-H…O hydrogen bond. The photoluminescence properties of complexes 1 and 2 were investigated.

Surface Anti-bacterial Adhesion Characteristics of TiO_2-coated PMMA

The anti-bacterial adhesion properties of TiO2-coated polymethyl methacrylate （PMMA） surfaces are investigated systematically. In detail, the adhesion of S. aureus （gram positive） and E. coli （gram negative） to TiO2-coated and uncoated PMMA surfaces are performed by the plate counting method. Afterwards, the adhesion free energy of bacteria on both supporting materials is quantified using the thermodynamic approach of Lifshitz van der Waals and acid/base interactions. The superior anti-adhesion capability of TiO2-coated PMMA is demonstrated when compared to native PMMA, both experimentally and theoretically.

Syntheses, Crystal Structures and Characterization of Two New Cadmium(II) Arsonates

Two cadmium arsonate coordination polymers, Cd（HL1）2 （1, H2L1 = 4-aminophenylarsonatic acid） and Cd（H2L2）2·2H2O （2, H3L2 = 2-（4-arsonphenylamino）acetic acid）, have been synthesized and characterized by IR and single-crystal X-ray diffraction. Crystal data for 1： triclinic, space group P1 with a = 5.7559（12）, b = 7.0903（14）, c = 8.9925（18）, α = 89.04（3）, β = 80.79（3）, γ = 85.09（3）o, Dc = 2.496 g·cm-3, μ = 6.095 mm-1, F（000） = 260, Z = 1, the final R = 0.0574 and wR = 0.1376 for 1489 observed reflections with I 〉 2σ（I）. And those for 2： monoclinic, space group P21/c with a = 4.7595（10）, b = 9.925（2）, c = 22.609（5）, β = 91.81（3）°, Dc = 2.167 g·cm-3, μ = 4.168 mm-1, F（000） = 684, Z = 2, the final R = 0.0335 and wR = 0.0815 for 2340 observed reflections with I 〉 2σ（I）. The structure of 1 shows a two-dimensional layer consisting of inorganic chains of {CdN2（AsO3）2} along the a axis linking with the phenyl groups. These layers are further linked through strong interlayer hydrogen bonding interaction to form a three-dimensional hydrogen bond supramolecular architecture. Compound 2 has inorganic chains of {CdO2（AsO3）2} similar to 1, which connect with four adjacent inorganic chains forming a three-dimensional framework.

Implementation of Controlled Geometric Phase Gate for Two Trapped Neutral Atoms

We propose a scheme for realizing a controlled geometric phase gate for two neutral atoms.We apply thestimulated Raman adiabatic passage to transfer atoms from their ground states into Rydberg excited states, and use theRydberg interaction induced energy shifts to generate geometric phase and construct quantum gates.

Hydrothermal Synthesis of CdIn_2S_4 and Photocatalytic Degradation of Methyl Orange under Visible-light Irradiation

CdIn2S4 microspheres were synthesized by a facile hydrothermal method with the temperature ranging from 120 to 200 ℃. X-ray diffraction, UV-vis diffuse reflectance spectroscopy, nitrogen sorption analysis, X-ray photoelectron spectroscopy, scanning electron microscopy and transmission electron microscopy were used to characterize the products. It was found that the crystallographic structure and optical property of the products synthesized at different temperature were almost the same. The SBEX of CdIn2S4 products decreased when the synthesized temperature increased, and the largest SBET was 33.16 m2 g-1 （120 ℃ sample）. The degradation of methyl orange （MO） under the visible-light irradiation had been used as a probe reaction to investigate the photocatalytic activity of the as-prepared CdIn2S4, which showed that the CdIn2S4 sample synthesized at 120 ℃ presented the best photocatalytic activity for MO degradation.

Electronic Structures and Optical Properties of HgGa_2X_4 (X=S,Se,Te)Semiconductors

The first-principles density functional calculations are performed to study the geometries and electronic structures of HgGa2X4（X = S,Se,Te） semiconductors with defect chalcopyrite structures,and the optical properties of all crystals are investigated systematically.The results indicate that these compounds have similar band structures and the band gap decreases from S to Se to Te.For the linear optical properties,three crystals show good light transmission in the IR and part visible regions,and in particular,HgGa2S4 and HgGa2Se4 crystals possess moderate birefringence.For the nonlinear optical properties,these crystals have stronger second harmonic generation（SHG）,and are theoretically predicted to have larger second-order static SHG coefficients（ 30 pm/V）.The SHG of HgGa2X4（X = S,Se,Te） semiconductors can be attributed to the transitions from the bands near the top of valence band derived from X（X = S,Se,Te） p states to the unoccupied bands contributed by the p states of Ga atoms.Our results indicate that the HgGa2S4 and HgGa2Se4 compounds are good candidates for nonlinear optical crystals in the IR region.

Scheme for direct measurement of Wigner function in two-mode cavity QED driven by classical fields

We propose a scheme for the direct measurement of Wigner function in two-mode cavity QED. The atoms are sent to resonantly interact with two orthogonally polarized cavity modes in the presence of strong classical field. The probability of measuring the atom in the ground state directly gives the useful information of the cavity field. This method can be used for quantum non-demolition measurement of the photon number.

Photocatalytic Activities for Water Splitting of RuO_2-loaded MGa_2O_4(M=Zn,Ni) with d^(10) Configuration

MGa2O4（M=Zn,Ni） rods with similar crystallinity and BET surface area were prepared via a facile template-engaged reaction.The photocatalytic activities for water splitting of RuO2-loaded MGa2O4（M=Zn,Ni） were investigated under high-pressure Hg lamp.RuO2-loaded ZnGa2O4 catalyst exhibited much higher photocatalytic activity than RuO2-loaded NiGa2O4.Factors affecting the photocatalytic activities of RuO2-loaded MGa2O4（M=Zn,Ni） were discussed.It was suggested that the electronic structure of oxide semiconductor was a predominant factor of the photocatalytic behavior for RuO2-loaded MGa2O4（M=Zn,Ni）.

Quantum communication and entanglement between two distant atoms via vacuum fields

This paper proposes an efficient scheme for quantum communication between two atoms trapped in distant cavities which are connected by an optical fibre. During the operation, all the atomic system, the cavity modes and the fibre are not excited. The quantum state is mediated by the vacuum fields. The idea can be used to realize quantum entanglement between two distant atoms via vacuum.

Pure water splitting to generate H_2 over strontium niobate and tantalate:A comparative study

To clarify the nature of different photocatalytic activities between niobate and tantalate,a comparative study of the water splitting into H2 over strontium niobate and tantalate was performed.These isostructural photocatalysts were prepared by a facile and simple hydrothermal reaction and characterized by powder X-ray diffraction(XRD),N2-sorption,UV-Vis diffuse reflectance spectra(UV-Vis DRS),and transmission electron microscopy(TEM).The effects of crystal structure,Brunauer-Emmett-Teller(BET) surface area,photoabsorption performance,morphology,and electronic structure are discussed.