Highly Efficient Storage of 25-Dimensional Photonic Qudit in a Cold-Atom-Based Quantum Memory.

Building an efficient quantum memory in high-dimensional Hilbert spaces is one of the fundamental requirements for establishing high-dimensional quantum repeaters, where it offers many advantages over two-dimensional quantum systems, such as a larger information capacity and enhanced noise resilience. To date, it remains a challenge to develop an efficient high-dimensional quantum memory. Here, we experimentally realize a quantum memory that is operational in Hilbert spaces of up to 25 dimensions with a storage efficiency of close to 60% and a fidelity of 84.

Telecom-wavelength conversion in a high optical depth cold atomic system.

We experimentally investigate the frequency down-conversion through the four-wave mixing (FWM) process in a cold Rb atomic ensemble, with a diamond-level configuration. An atomic cloud with a high optical depth (OD) of 190 is prepared to achieve a high efficiency frequency conversion. Here, we convert a signal pulse field (795 nm) attenuated to a single-photon level, into a telecom light at 1529.

Optical memory for arbitrary perfect Poincaré states in an atomic ensemble.

Inherent spin angular momentum (SAM) and orbital angular momentum (OAM), which manifest as polarization and spatial degrees of freedom (DOFs) of photons, hold a promise of large capability for applications in classical and quantum information processing. To enable these photonic spin and orbital dynamic properties strongly coupled with each other, Poincaré states have been proposed and offer advantages in data multiplexing, information encryption, precision metrology, and quantum memory. However, since the transverse size of Laguerre-Gaussian beams strongly depends on their topological charge numbers | l |, it is difficult to store asymmetric Poincaré states due to the significantly different light-matter interaction for distinct spatial modes.

Long-Lived Memory for Orbital Angular Momentum Quantum States.

Quantum memories that are capable of storing multiple spatial modes offer advantages in speed and robustness when incorporated into quantum networks. When it comes to spatial degrees of freedom, orbital angular momentum (OAM) modes have received widespread attention since they enable encoding with inherent infinite number of dimensions. Although the faithful storage of OAM qubits or qutrits has been realized in previous works, the achieved lifetimes are still on the order of a few microseconds as limited by the spatially dependent decoherence.

Microglial Polarization: Novel Therapeutic Strategy against Ischemic Stroke.

Ischemic stroke, which is the second highest cause of death and the leading cause of disability, represents ~71% of all strokes globally. Some studies have found that the key elements of the pathobiology of stroke is immunity and inflammation. Microglia are the first line of defense in the nervous system.

All-optical reversible single-photon isolation at room temperature.

Nonreciprocal devices operating at the single-photon level are fundamental elements for quantum technologies. Because magneto-optical nonreciprocal devices are incompatible for magnetic-sensitive or on-chip quantum information processing, all-optical nonreciprocal isolation is highly desired, but its realization at the quantum level is yet to be accomplished at room temperature. Here, we propose and experimentally demonstrate two regimes, using electromagnetically induced transparency (EIT) or a Raman transition, for all-optical isolation with warm atoms.

Nrf2 played an important role in radiation protection effect of low-level laser exposed on umbilical cord mesenchymal stem cell.

To investigate the protective function of low-level laser irradiation (LLLI) against ionizing irradiation and explore the molecular mechanism of photomodulation of Nrf2 protein, the impact of LLLI (635 nm, 5.7 J/cm) before 2 Gy gamma ray radiation of radio-sensitive tissue hematopoietic stem cells was evaluated. As a result, reduced levels of reactive oxygen species and increased expression of antioxidant enzymes were detected.

Experimental realization of optical storage of vector beams of light in warm atomic vapor.

Vector beams have drawn considerable interest recently because of their unique properties in the transverse plane. Here we experimentally realize optical storage of a vector beam of light in a warm cell. The vector beam is tailored using a Sagnac interferometer containing an internal vortex phase plate, and the light pulse is stored in warm rubidium vapor.

Experimental realization of narrowband four-photon Greenberger-Horne-Zeilinger state in a single cold atomic ensemble.

Multi-photon entangled states not only play a crucial role in research on quantum physics but also have many applications in quantum information fields such as quantum computation, quantum communication, and quantum metrology. To fully exploit the multi-photon entangled states, it is important to establish the interaction between entangled photons and matter, which requires that photons have narrow bandwidth. Here, we report on the experimental generation of a narrowband four-photon Greenberger-Horne-Zeilinger state with a fidelity of 64.

Two-color hyper-entangled photon pairs generation in a cold Rb atomic ensemble.

Hyper-entangled photon pairs are very promising in the quantum information field for enhancing the channel capacity in communication and improving compatibility for networks. Here we report on the experimental generation of a hyper-entangled photon pair at a wavelength of 795 nm and 1475 nm via the spontaneous four-wave mixing process in a cold Rb atomic ensemble. The photons in each pair generated are entangled in both the time-frequency and polarization degrees of freedom.

Experimental realization of entanglement in multiple degrees of freedom between two quantum memories.

Entanglement in multiple degrees of freedom has many benefits over entanglement in a single one. The former enables quantum communication with higher channel capacity and more efficient quantum information processing and is compatible with diverse quantum networks. Establishing multi-degree-of-freedom entangled memories is not only vital for high-capacity quantum communication and computing, but also promising for enhanced violations of nonlocality in quantum systems.

Orbital Angular Momentum-Entanglement Frequency Transducer.

Entanglement is a vital resource for realizing many tasks such as teleportation, secure key distribution, metrology, and quantum computations. To effectively build entanglement between different quantum systems and share information between them, a frequency transducer to convert between quantum states of different wavelengths while retaining its quantum features is indispensable. Information encoded in the photon's orbital angular momentum (OAM) degrees of freedom is preferred in harnessing the information-carrying capacity of a single photon because of its unlimited dimensions.

Design, synthesis, and biological activity of novel 1,4-disubstituted piperidine/piperazine derivatives as CCR5 antagonist-based HIV-1 entry inhibitors.

A series of novel 1,4-disubstituted piperidine/piperazine derivatives were designed, synthesized and evaluated for their in vitro activities against HIV-1 Bal (R5) infection in CEMX174 5.25M7 cells. A majority of these compounds showed potent anti-HIV-1 activities with IC(50) at nanomolar levels.

Tricyclononene carboxamide derivatives as novel anti-HIV-1 agents.

By modifying the chemical structure of anti-orthopoxvirus compound ST-246, we designed and synthesized a series of tricyclononene carboxamide derivatives and tested their anti-HIV-1 activity and cytotoxicity. We found that benzoimidazol-containing compound 7g was highly effective in inhibiting HIV-1 R5 infection with an IC(50) value of 0.41 microM and a selectivity index of 292, but it exhibited no significant inhibitory activity on HIV-1 reverse transcriptase, integrase and protease.