Tunable photon blockade in a hybrid system consisting of an optomechanical device coupled to a two-level system

We study photon blockade and anti-bunching in the cavity of an optomechanical system in which the mechanical resonator is coupled to a two-level system (TLS). In particular, we analyze the effects of the coupling strength (to the mechanical mode), transition frequency, and decay rate of TLS on the photon blockade. The statistical properties of the cavity field are affected by the TLS, because the TLS changes the energy-level structure of the optomechanical system via dressed states formed by the TLS and the mechanical resonator. We find that the photon blockade and tunneling can be significantly changed by the transition frequency of the TLS and the coupling strength between the TLS and the mechanical resonator. Therefore, our study provides a method to tune the photon blockade and tunneling using a controllable TLS.Comment: 11 page

Decacarbonyl-1κ3 C,2κ3 C,3κ4 C-μ-hydrido-1:2κ2 H:H-(μ-quinoline-2-thiol­ato-1:2κ2 S:S)diosmium(I)osmium(0)(3 Os—Os)

The title compound, [Os3(C9H6NS)H(CO)10], contains a nearly equilateral triangle of Os atoms. Two of the Os atoms are bridged by an S atom of the quinoline-2-thiol­ate ligand. Ten carbonyl groups complete the cluster, resulting in a distorted octa­hedral geometry for each Os atom. The hydride atom, which was located in a difference Fourier map and refined isotropically, bridges the shortest Os–Os edge

Bis(μ-cyclo­hexane-1,4-dicarboxyl­ato)bis­{aqua­[1-(1H-imidazo[4,5-f][1,10]phenanthrolin-2-yl)naphthalen-2-ol]cadmium} monohydrate

The asymmetric unit of the title compound, [Cd2(C8H10O4)2(C23H14N4O)2(H2O)2]·H2O, consists of one half of the dimeric complex, which lies about an inversion centre, and a half-occupancy solvent water mol­ecule on a general position. Each CdII cation is six-coordinated by the two N atoms from one 1-(1H-imidazo[4,5-f][1,10]phenanthrolin-2-yl)naphthalen-2-ol (L) ligand and three O atoms from two different 1,4-chdc2− ligands (1,4-H2chdc = cyclo­hexane-1,4-dicarb­oxy­lic acid), two coordinating in a bidentate fashion and the other in a monodentate fashion. The distorted octa­hedral coordination sphere is completed by a coordinated water mol­ecule. The CdII atoms are each bridged by two 1,4-chdc2− ligands, forming an inversion dimer with the L ligands located on the outside of the dimeric unit. An intra­molecular N—H⋯O hydrogen bond occurs. In the crystal, O—H⋯O and N—H⋯O hydrogen-bonding inter­actions stabilize the packing

Expressions of toll-like receptors 2 and 4, and relative cellular factors in HIV patients with tuberculosis infection

Purpose: To investigate the expressions of toll-like receptor 2 (TLR2), toll-like receptor 4 (TLR4), tumor necrosis factor alpha (TNF-α), IFN-γ (IFN- gamma), interleukin 2 (IL-2), interleukin 6 (IL-6) and interleukin 10 (IL-10) in human immunodeficiency virus (HIV) patients with tuberculosis (TB) infection.Methods: Two groups of HIV patients (68 in each group) were used for this study. These were HIV with TB (HIV/TB) group and HIV without TB group. A third group (68 healthy people) served as control. Quantitative polymerase chain reaction (qPCR) was adopted to measure TLR-2 and TLR-4 expressions in peripheral blood mononuclear cells (PBMC), while the serum levels of TNF-α, IFN-γ, IL-2, IL-6 and IL-10 were determined by ELISA.Results: The △Ct values of TLR-2 and TLR-4 in HIV/TB and HIV groups were significantly lower than those in the control group (p < 0.05). Compared to control group, the serum levels of TNF-α, IL-6 and IL-10 significantly increased, while IFN-γ and IL-2 in HIV/TB and HIV groups significantly decreased (p < 0.05). However, IFN-γ and IL-2 decreased significantly in HIV/TB group (p < 0.05). Expression of TLR2 correlated positively with serum levels of TNF-α, IL-6 and IL-10, but negatively with IFN-γ and IL-2 (p < 0.05).Conclusion: TLR2 signal pathway plays a role in HIV patients with TB infection by promoting the expressions of TNF-α, IL-6 and IL-10, while inhibiting IFN-γ and IL-2 cellular factors, and thus may provide a new pathway for the treatment of patients with HIV/TB.Keywords: HIV, Tuberculosis, Toll-like receptor, Cellular factors, Tumor necrosis factor, Interleuki

Topological edge state transfer via topological adiabatic passage

The study of quantum state transfer has led to a variety of research efforts utilizing quantum simulators. By exploiting the tunability of the qubit frequency and qubit-qubit coupling, a superconducting qubit chain can simulate various topological band models. In our study, we demonstrate that a spin-up state can be transported along a topological qubit chain by modulating the coupling strengths and the qubit frequencies. We here propose another more straightforward approach to theoretically interpret this state transfer process. We show that the Hilebert space of the qubit chain can be restricted into the subspace of the only two edge states when investigating this process, and the Hamiltonian can degenerate to a two-state Landau-Zener (LZ) model. Therefore the state transfer process in this topological qubit chain is equivalent to the same process through the adiabatic passage of the LZ model. Further more, we show how to use this approach to generalize the state transfer process from one-qubit Fock state to two-qubit Bell state.Comment: arXiv admin note: substantial text overlap with arXiv:1711.0682

Design of Virtual Objects Using Transformation Optics

Two structures of virtual targets filled with metamaterials are investigated through transformation optics to tailor the specific electromagnetic fields into desired spatial patterns. One virtual structure is a square column object transformed from a dielectric cylinder and the other virtual structure is a cylinder object transformed from a dielectric square column. Because the electromagnetic parameters in the virtual objects are obtained from real objects by the method of transformation optics, the scattering fields of virtual structures are the same as those of the real objects. The numerical simulations further prove the correction of theoretical results