Black phosphorus, or BP, has found a lot of applications in recent years including photonics. The most recent studies have shown that the material has an excellent optical nonlinearity useful in many areas, one of which is in saturable absorption for passive mode‐locking. A direct interaction scheme for mode‐locking, however, has a potential to optically cause permanent damage to the already delicate material. Evanescent field interaction scheme has already been proven to be a useful method to prevent such danger for other 2‐dimensional nanomaterials. In this report, we have utilized the evanescent field interaction to demonstrate that the optical nonlinear characteristics of BP is sufficiently strong to use in such an indirect interaction method. The successful demonstration of the passive mode‐locking operation has generated pulses with the pulse duration, repetition rate, and time bandwidth product of 2.18 ps, 15.59 MHz, and 0.336, respectively.

The outstanding electronic and optical properties of black phosphorus (BP) in a two-dimensional (2D) but unique single-layer puckered structure have opened intense research interest ranging from fundamental physics to nanoscale applications covering the electronic and optical domains. The direct and controllable electronic bandgap facilitating wide range of tunable optical response coupled with high anisotropic in-plane properties made BP a promising nonlinear optical material for broadband optical applications. Here, we investigate ultrafast optical switching relying on the optical nonlinearity of BP. Wavelength conversion for modulated signals whose frequency reaches up to 20 GHz is realized by four-wave-mixing (FWM) with BP-deposited D-shaped fiber. In the successful demonstration of the FWM based wavelength conversion, performance parameter has been increased up to ~33% after employing BP in the device. It verifies that BP is able to perform efficient optical switching in the evanescent field interaction regime at very high speed. Our results might suggest that BP-based ultra-fast photonics devices could be potentially developed for broadband applications.

In the recent past, 2D black phosphorus (BP) has been intensively studied and examined due to its unique electronic, photonic, and mechanical properties. The tunable and moderate direct bandgap and the high carrier mobility of BP provide enormous potential in electronic and optoelectronic applications. In addition, the unique intrinsic anisotropic characteristics resulting from the puckered structure yield remarkable optical, electronic, transport, mechanical, and thermal characteristics that can be utilized for designing new devices. Significant efforts have been directed toward the synthesis, basic understanding, and applications of BP in the fields of nanoelectronics, ultrafast optics, nanophotonics, and optoelectronics. Here, the current development of electronic, photonic, optoelectronic, and optical devices based on BP is summarized, along with the recent advances in investigating its electronic, optical, and mechanical properties, which form the foundation for next‐generation chip‐scale integrated devices. In addition, a comprehensive discussion on the requirements for forthcoming studies to upgrade well‐systemized fabrication techniques toward large‐area, high‐yield, and perfectly shielded BP‐film production for the development of reliable devices in optoelectronic applications and other areas is provided. Finally, some existing challenges in implementing BP‐based optoelectronic and photonic devices are addressed and the prospects for future BP‐related research are discussed.

BackgroundGinsenosides are the main ingredients of ginseng, which, in traditional Eastern medicine, has been claimed to have therapeutic values for many diseases. In order to verify the effects of ginseng that have been empirically observed, we utilized the reverse docking method to screen for target proteins that are linked to specific diseases.MethodsWe constructed a target protein database including 1,078 proteins associated with various kinds of diseases, based on the Potential Drug Target Database, with an added list of kinase proteins. We screened 26 kinds of ginsenosides of this target protein database using docking.ResultsWe found four potential target proteins for ginsenosides, based on docking scores. Implications of these “hit” targets are discussed. From this screening, we also found four targets linked to possible side effects and toxicities, based on docking scores.ConclusionOur method and results can be helpful for finding new targets and developing new drugs from natural products.

Recent studies of black phosphorus (BP) have shown its future potential in the field of photonics. We determined the optical damage threshold of BP at 21.8 dBm in a fiber ring laser cavity, and demonstrated the high-power operation capacity of an evanescent field interaction-based BP saturable absorber. The long-term stability of a passively mode-locked fiber laser with a saturable absorber operating at the optical power of 23.3 dBm was verified for 168 h without any significant performance degradation. The center wavelength, spectral width, and pulse width of the laser output are 1558.8 nm, 14.2 nm, and 805 fs, respectively.