CLP wishes you all the best in the New Year of 2023!
Researchers from École Polytechnique Fédérale de Lausanne (EPFL) proposed a deep neural network to solve the optical scattering problem and used this neural network as a surrogate forward model in the iterative reconstruction of the optical diffraction tomography. The image on the cover for Advanced Photonics Volume 4 Issue 6 provides a visual representation of this physics-informed deep neural network used for 3D optical imaging.
This paper demonstrates the production of the high-finesse optical fiber microcavity for the Rb<sub>2</sub> molecule cavity QED experiment, which includes the fabrication of fiber-based cavity mirrors, testing, and the assembly of ultra-high vacuum-compatible optical fiber microcavity. The optical fiber microcavity offers high cooperativity between cavity mode and ultracold molecule and paves the way for the study of molecule cavity QED experimental research.
This paper shows the feasibility of a wavelength-division multiplexing FSO communication system which suits the ultra-high-speed wireless transmission application scenarios in future satellite-based communications, disaster recovery, defense, last mile problems in networks and remote sensing, and so on.
Researchers from The Chinese University of Hong Kong and University of Science and Technology of China proposed a new scheme of coherent wavelength conversion with simple experimental requirements and an enhanced operating bandwidth. In their work, “Highly tunable broadband coherent wavelength conversion with a fiber-based optomechanical system,” authors Xiang Xi, Chang-Ling Zou, Chun-Hua Dong, and Xiankai Sun report experimental realization of coherent information transfer between two orthogonally propagating light beams of disparate wavelengths in a fiber-based optomechanical system by demonstrating broadband optomechanically induced transparency and absorption with high tunability.
Epitaxial quantum dots formed by III–V compound semiconductors are excellent sources of non-classical photons, creating single photons and entangled multi
Epitaxial quantum dots formed by III–V compound semiconductors are excellent sources of non-classical photons, creating single photons and entangled multi-photon states on demand. Their semiconductor nature allows for a straightforward combination with mature integrated photonic technologies, leading to novel functional devices at the single-photon level. Integrating a quantum dot into a carefully engineered photonic cavity enables control of the radiative decay rate using the Purcell effect and the realization of photon–photon nonlinear gates. In this review, we introduce the basis of epitaxial quantum dots and discuss their applications as non-classical light sources. We highlight two interfaces—one between flying photons and the quantum-dot dipole, and the other between the photons and the spin. We summarize the recent development of integrated photonics and reconfigurable devices that have been combined with quantum dots or are suitable for hybrid integration. Finally, we provide an outlook of employing quantum-dot platforms for practical applications in large-scale quantum computation and the quantum Internet.show less
Recent interest in developing fast spintronic devices and laser-controllable magnetic solids has sparked tremendous experimental and theoretical efforts t
Recent interest in developing fast spintronic devices and laser-controllable magnetic solids has sparked tremendous experimental and theoretical efforts to understand and manipulate ultrafast dynamics in materials. Studies of spin dynamics in the terahertz (THz) frequency range are particularly important for elucidating microscopic pathways toward novel device functionalities. Here, we review THz phenomena related to spin dynamics in rare-earth orthoferrites, a class of materials promising for antiferromagnetic spintronics. We expand this topic into a description of four key elements. (1) We start by describing THz spectroscopy of spin excitations for probing magnetic phase transitions in thermal equilibrium. While acoustic magnons are useful indicators of spin reorientation transitions, electromagnons that arise from dynamic magnetoelectric couplings serve as a signature of inversion-symmetry-breaking phases at low temperatures. (2) We then review the strong laser driving scenario, where the system is excited far from equilibrium and thereby subject to modifications to the free-energy landscape. Microscopic pathways for ultrafast laser manipulation of magnetic order are discussed. (3) Furthermore, we review a variety of protocols to manipulate coherent THz magnons in time and space, which are useful capabilities for antiferromagnetic spintronic applications. (4) Finally, new insights into the connection between dynamic magnetic coupling in condensed matter and the Dicke superradiant phase transition in quantum optics are provided. By presenting a review on an array of THz spin phenomena occurring in a single class of materials, we hope to trigger interdisciplinary efforts that actively seek connections between subfields of spintronics, which will facilitate the invention of new protocols of active spin control and quantum phase engineering.show less
The luminescent materials often suffer from thermal quenching (TQ), limiting the continuation of their applications under high temperatures up to 473 K. The formation of defect levels c
The luminescent materials often suffer from thermal quenching (TQ), limiting the continuation of their applications under high temperatures up to 473 K. The formation of defect levels could suppress TQ, but rational synthesis and deep understanding of multiple defects-regulated luminescent materials working in such a wide temperature range still remain challenging. Here, we prepare a negative thermal quenching (NTQ) phosphor LiTaO3:Tb3+ by introducing gradient defects V_Ta^(5-), Tb_Li^(2+), and 〖(V〗_Ta Tb_Li)3- as identified by advanced experimental including atomic-scale electron microscopy, positron annihilation lifetime spectroscopy, thermoluminescence, etc. Its photoluminescence significantly goes intensity with rising temperature and then slowly increases at 373-473 K. Combined with theoretical calculations, the mechanism studies reveal that gradient-defects with varied trapping-depths could act as energy buffer layers to effectively capture the carriers. Under thermal disturbance, the stored carriers could successively migrate to the activators in consecutive and wide temperature zones, compensating for TQ to enhance luminescence emission. This study initiates LiTaO3:Tb3+ with gradient defects-induced NTQ demonstrating broad application prospects in temperature-dependent anti-counterfeiting and optical information storage.show less
As optical parametric chirped pulse amplification (OPCPA) has been widely adopted for the generation of extreme intensity laser sources, nonlinear crystals of large aperture are demande
As optical parametric chirped pulse amplification (OPCPA) has been widely adopted for the generation of extreme intensity laser sources, nonlinear crystals of large aperture are demanded for high energy amplifiers. Yttrium calcium oxyborate (YCa4O(BO3)3, YCOB) is capable to be grown with aperture exceeding hundred millimeters, which makes it possible for application in systems of petawatt scale. In this paper, we experimentally demonstrated for the first time to our knowledge, an ultra-broadband non-collinear optical parametric amplifier with YCOB for petawatt scale compressed pulse generation at 800 nm. Based on SG-Ⅱ 5PW facility, amplified signal energy of ~40 J was achieved and pump-to-signal conversion efficiency was up to 42.3%. A gain bandwidth of 87 nm was realized and supported compressed pulse duration of 22.3 fs. The near field and wavefront aberration represented excellent characteristics which were comparable with those achieved in LBO-based amplifier. Those results verified YCOB great potential utilization in future.show less
A high-energy 100-Hz optical parametric oscillator (OPO) based on a confocal unstable resonator with Gaussian reflectivity mirror (GRM) was demonstrated. A KTA-based OPO with a good bea
A high-energy 100-Hz optical parametric oscillator (OPO) based on a confocal unstable resonator with Gaussian reflectivity mirror (GRM) was demonstrated. A KTA-based OPO with a good beam quality was obtained when the magnifications factor was 1.5, corresponding to the maximum signal (1.53 μm) energy of 56 mJ and idler (3.47 μm) energy of 20 mJ, respectively. The beam quality factors (M2) were measured to be M2 x=5.7, M2 y=5.9 for signal and M2 x=8.4, M2 y=8.1 for idler accordingly. The experimental results indicated that the beam quality positively changed with the increase of magnifications factors, accompanied by an acceptable loss of pulse energy.show less
The microring resonator based on Lithium niobate on insulator (LNOI) is a promising platform for broadband nonlinearity process, because of its strong second-order nonlinear coefficient
The microring resonator based on Lithium niobate on insulator (LNOI) is a promising platform for broadband nonlinearity process, because of its strong second-order nonlinear coefficients, the capability of dispersion engineering, etc. It is important to control the energy transmitted into the resonator at different wavelengths as this becomes difficult for two bands across an octave. In this letter, we study the effect of different pulley bus-resonator configurations on phase mismatching and mode field overlap. We achieve the control of energy transmission coefficients at different wavebands simultaneously and provide a general design methodology for coupled structures for broadband applications. This paper can contribute to quantum and classical optical broadband applications based on LNOI microring resonators.show less