Non-reciprocal optical components are indispensable in optical applications, and their realization without any magnetic field has attracted increasing research interest in photonics. Exciting experimental progress has been achieved by either introducing spatial-temporal modulation of the optical medium or combining Kerr-type optical nonlinearity with spatial asymmetry in photonic structures. However, extra driving fields are required for the first approach, while the isolation of noise and the transmission of the signal cannot be simultaneously achieved for the other approach.
View Article and Find Full Text PDFWe report on the experimental realization of a standing-wave atom tweezer (SWAT) by aligning tightly focused dipole laser beams from a commercial objective lens and a metalens on a chip. By independently tuning the laser intensities of the two beams, we demonstrate the controlled loading of multiple atoms into the SWAT. We systematically investigate the influence of the standing-wave potential modulation depth on single-atom loading dynamics and quantitatively estimate the number of atoms in the SWAT by calculating the fluorescence of trapped atoms.
View Article and Find Full Text PDFThe fluorescence collection from single atoms and emitters has been extensively utilized in quantum information and quantum optics research. Here, we investigated the collection efficiency of an objective lens by drawing an analogy between the free-space beam (FSB) and a waveguide mode. We explored how efficiency is influenced by their thermal motion within a dipole trap.
View Article and Find Full Text PDFMagnetic-free nonreciprocal optical devices have attracted great attention in recent years. Here, we investigated the magnetic-free polarization rotation of light in an atom vapor cell. Two mechanisms of magnetic-free nonreciprocity have been realized in ensembles of hot atoms, including electromagnetically induced transparency and optically-induced magnetization.
View Article and Find Full Text PDFHost plants play an important role in the growth, development, and reproduction of insects. However, only a few studies have reported the effects of maize varieties on the growth and reproduction of . In this study, a free-choice test was used to evaluate the oviposition preferences of female adults on ten common maize varieties and ten special maize varieties.
View Article and Find Full Text PDFThe transportation of photons and phonons typically obeys the principle of reciprocity. Breaking reciprocity of these bosonic excitations will enable the corresponding nonreciprocal devices, such as isolators and circulators. Here, we use two optical modes and two mechanical modes in a microresonator to form a four-mode plaquette via radiation pressure force.
View Article and Find Full Text PDFMechanical degrees of freedom, which have often been overlooked in various quantum systems, have been studied for applications ranging from quantum information processing to sensing. Here, we develop a hybrid platform consisting of a magnomechanical cavity and an optomechanical cavity, which are coherently coupled by the straightway physical contact. The phonons in the system can be manipulated either with the magnetostrictive interaction or optically through the radiation pressure.
View Article and Find Full Text PDFUltra-high resolution mass sensing used to be realized by measuring the changed mechanical oscillation frequency by a small mass that should be detected. In this work we present a different approach of mass sensing without directly measuring such mechanical frequency change but relying on the modified light field due to a previously less explored nonlinear mechanism of optomechanical interaction. The concerned optomechanical setup used for the mass sensing is driven by a sufficiently strong two-tone field satisfying a condition that the difference of these two drive frequencies matches the frequency of the mechanical oscillation, so that a nonlinear effect will come into being and lock the mechanical motion under the radiation pressure into a series of fixed orbits.
View Article and Find Full Text PDFSynchronization and frequency locking between remote mechanical oscillators are of scientific and technological importance. The key challenges are to align the oscillation frequencies and realize strong nonlinear interaction of both oscillators to a common carrier capable of long-distance transmission. Here, we experimentally realize the all-optical synchronization between two different optomechanical systems, a microsphere and a microdisk.
View Article and Find Full Text PDFIn an optomechanical system, we experimentally engineer the optical density of state to reduce or broaden the effective linewidth of the optical mode by introducing an ancillary mechanical mode, which has a large decay rate, i.e., stimulated backward Brillouin scattering.
View Article and Find Full Text PDFThe realization of optical non-reciprocity is crucial for many applications, and also of fundamental importance for manipulating and protecting the photons with desired time-reversal symmetry. Recently, various new mechanisms of magnetic-free non-reciprocity have been proposed and implemented, avoiding the limitation of the strong magnetic field imposed by the Faraday effect. However, due to the difficulties in separating the signal photons from the drive laser and the noise photons induced by the drive laser, these devices exhibit limited isolation performances and their quantum noise properties are rarely studied.
View Article and Find Full Text PDFSynthetic gauge fields have recently emerged, arising in the context of quantum simulations, topological matter, and the protected transportation of excitations against defects. For example, an ultracold atom experiences a light-induced effective magnetic field when tunneling in an optical lattice, and offering a platform to simulate the quantum Hall effect and topological insulators. Similarly, the magnetic field associated with photon transport between sites has been demonstrated in a coupled resonator array.
View Article and Find Full Text PDFBackground: In clinical applications of CAR T-cell therapy, life-threatening adverse events including cytokine release syndrome and neurotoxicity can lead to treatment failure. Outcomes of patients treated with anti-CD30 CAR T- cell have been disappointing in relapsing/refractory (r/r) classical Hodgkin's Lymphoma (cHL).
Methods: In order to understand the applicable population of multiple CAR T-cell therapy, we examined the expression of CD19, CD20, and CD30 by immunohistochemistry (IHC) in 38 paraffin-embedded specimens of cHL.
We propose how to achieve nonreciprocal quantum entanglement of light and motion and reveal its counterintuitive robustness against random losses. We find that by splitting the counterpropagating lights of a spinning resonator via the Sagnac effect, photons and phonons can be entangled strongly in a chosen direction but fully uncorrelated in the other. This makes it possible both to realize quantum nonreciprocity even in the absence of any classical nonreciprocity and also to achieve significant entanglement revival against backscattering losses in practical devices.
View Article and Find Full Text PDFNonlinear optical effects in integrated microcavities have been studied extensively with the advantages of strong light-matter interaction, great scalability, and stability due to the small mode volume. However, the pump lasers stimulating nonlinear effects impose obstacles for practical applications, since the material absorption causes thermal resonance drift and instability. Here we experimentally demonstrate an all-optical control of the thermal behavior in optical microcavities for tunable doubly-resonant second-harmonic (SH) generation on an integrated photonic chip.
View Article and Find Full Text PDFHere in this work, porous carbon is prepared from waste of a traditional Chinese medicine Salvia miltiorrhiza flowers. Structures of the porous carbons are regulated by simply regulating of activation temperatures and dosages of activator. The optimized porous carbon owns a high specific surface area of 1715.
View Article and Find Full Text PDFZhongguo Zhong Yao Za Zhi
October 2019
With digital satellite remote sensing image data of GF-1,in 2018 the object-oriented classification method was used to extract Zizyphus jujuba planting area in Jia county of Shaanxi province. The results showed that the remote sensing classification method based on rule set could extract and reckon Z. jujube planting area in the study area effectively.
View Article and Find Full Text PDFCavity-enhanced optical controlling is experimentally observed with a low-control laser power in a cavity-atom ensemble system. Here, the three-level atoms are coupled with two optical modes of a Fabry-Perot cavity, where a new theoretical model is developed to describe the effective three-wave mixing process between spin-wave and optical modes. By adjusting either temperature or cavity length, we demonstrate the precise frequency tuning of the hybrid optical-atomic resonances.
View Article and Find Full Text PDFNon-reciprocal devices, which allow non-reciprocal signal routing, serve as fundamental elements in photonic and microwave circuits and are crucial in both classical and quantum information processing. The radiation-pressure-induced coupling between light and mechanical motion in travelling-wave resonators has been exploited to break the Lorentz reciprocity, enabling non-reciprocal devices without magnetic materials. Here, we experimentally demonstrate a reconfigurable non-reciprocal device with alternative functions as either a circulator or a directional amplifier via optomechanically induced coherent photon-phonon conversion or gain.
View Article and Find Full Text PDFSynchronization is of great scientific interest due to the abundant applications in a wide range of systems. We propose an all-optical scheme to achieve the controllable long-distance synchronization of two dissimilar optomechanical systems, which are unidirectionally coupled through a fiber with light. Synchronization, unsynchronization, and the dependence of the synchronization on driving laser strength and intrinsic frequency mismatch are studied based on the numerical simulation.
View Article and Find Full Text PDFGrassbur is a destructive and invasive weed in pastures, and its burs can cause gastric damage to animals. The strong adaptability and reproductive potential of grassbur are partly due to a unique germination mechanism whereby twin seeds develop in a single bur: one seed germinates, but the other remains dormant. To investigate the molecular mechanism of seed germination in twin seeds, we used isobaric tags for relative and absolute quantitation (iTRAQ) to perform a dynamic proteomic analysis of germination and dormancy.
View Article and Find Full Text PDFWe propose a new approach to realize all-optical circulator based on stimulated Brillouin scattering in an integrated microresonator. Stimulated Brillouin scattering is a basic interaction between photon and traveling acoustic wave resulted from electrostriction and photoelastic effects. Due to the phase-matching requirement, the circulating acoustic wave can only couple to probe light which propagating along or opposite to the pump laser direction, thus exhibits a non-reciprocal phase shift.
View Article and Find Full Text PDFStimulated Brillouin scattering is a fundamental interaction between light and travelling acoustic waves and arises primarily from electrostriction and photoelastic effects, with an interaction strength several orders of magnitude greater than that of other relevant non-linear optical processes. Here we report an experimental demonstration of Brillouin-scattering-induced transparency in a high-quality whispering-gallery-mode optical microresonantor. The triply resonant Stimulated Brillouin scattering process underlying the Brillouin-scattering-induced transparency greatly enhances the light-acoustic interaction, enabling the storage of light as a coherent, circulating acoustic wave with a lifetime up to 10 μs.
View Article and Find Full Text PDFA general and efficient palladium-catalyzed intermolecular direct C-H homocoupling of furans and thiophenes has been developed. The reaction is characterized by using molecular oxygen as the sole oxidant and complete C5-position regioselectivity. Both C2- and C3-substituted furans or thiophenes are appropriate substrates.
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