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<jats:p>We demonstrate a novel and stable frequency transfer scheme over ground-to-satellite link based on real-time carrier-phase detection and compensation. We performed a zero-baseline measurement with the designed system, an uninterrupted frequency standard signal is recovered in the reception station without additional post-correction of delay error caused in the route, which is because the phase error of the entire route is tracked and compensated continuously in real-time. To achieve this goal, we employed two carriers in the system and the differential signal is transferred in order to eliminate the instability results from the local oscillator at the satellite transponder as well as the common-mode noise induced in the transfer route and microwave components. The stability of 3 × 10<jats:sup>−16</jats:sup> with an integration time of 1 day was achieved and the time fluctuation during one day was measured to be about ±20 ps. Error sources and possible solutions are discussed. Our zero-baseline method shows a promising result for real-time satellite-based time and frequency transfer and deserves further research to find whether it works between long-baseline stations.</jats:p>

<jats:p>A method of detecting the single channel triaxial magnetic field information based on diamond nitrogen-vacancy (NV) color center is introduced. Firstly, the incident angle of the bias magnetic field which can achieve the equal frequency difference optically-detected magnetic resonance (ODMR) spectrum of diamond NV color center is calculated theoretically, and the triaxial magnetic information solution model is also constructed. Secondly, the microwave time-controlled circuit module is designed to generate equal timing and equal frequency difference microwave pulse signals in one channel. Combining with the optical detection magnetic resonance technology, the purpose of sequentially locking and detecting the four formant signals on one side of the diamond NV color center (<jats:italic>m</jats:italic> <jats:sub>s</jats:sub> = –1 state signal) is achieved, and the vector magnetic field information detection is accomplished by combining the triaxial magnetic information solution model. The system can obtain magnetic field detection in a range of 0 mT–0.82 mT. The system’s magnetic noise sensitivity is 14.2 nT/Hz<jats:sup>1/2</jats:sup>, and the deviation angle errors of magnetic field detection <jats:italic>θ<jats:sub>x</jats:sub> </jats:italic> and <jats:italic>θ<jats:sub>y</jats:sub> </jats:italic> are 1.3° and 8.2° respectively.</jats:p>

<jats:p>A two-dimensional dose detector for ion beam is required in many high energy density physics experiments. As a solid detector, the GAFChromic film offers a good spatial resolution and dosimetric accuracy. For an absolute dose measurement, the relative effectiveness, which represents the darkening efficiency of the film to a radiation source, needs to be taken into consideration. In this contribution, the dose-response of HD-V2 to argon ions is presented for the first time. The calibration was taken over the dose range of 65 Gy–660 Gy with 8-keV argon ions. The response of net optical density is from 0.01 to 0.05. Triple-color dose-response functions are derived. The relative effectiveness for the argon ion beams is about 5%, much lower than that of protons and carbon ions. To explain this effect, the inactivation probability based on track theory of ion bombardment is proposed. Furthermore, a theoretical prediction of the relative effectiveness for single ion is presented, showing the dependence of the darkening efficiency on the atomic number and the incident energy of ions.</jats:p>

<jats:p>Graphene has excellent thirdorder nonlinear optical (NLO) properties due to its unique electronic band structure and wideband gap tunability. This paper focuses on the research progress of graphene and its composite materials in nonlinear optics in recent years. In this review, recent results on graphene (or graphene oxide)–metal nanoparticles (G-MNPs), graphene–metal–oxide nanoparticles (G-MONPs), graphene–metal sulfide nanoparticles (G-MSNPs), and graphene–organic molecular composites (G-OM) have been discussed. In addition, the enhancement mechanism of nonlinear absorption (NLA) and optical limiting (OL) have also been covered.</jats:p>

<jats:p>The pursuit of a systematic frequency uncertainty beyond 10<jats:sup>−18</jats:sup> clock has triggered a multitude of investigations on the multipolar and higher-order lattice light shifts. The Cd atom has been proposed as a new candidate for the development of a lattice clock because of its smaller blackbody radiation shift at room temperature. Here, we apply an improved combined method of the Dirac–Fock plus core polarization and relativistic configuration interaction methods to calculate the dynamic multipolar polarizabilities of the Cd clock states. The effects of the high-order core-polarization potentials on the energies, reduced matrix elements, and multipolar polarizabilities have been evaluated systematically. The detailed comparison with available literature demonstrates that taking into account of the high-order core-polarization potentials is a simple and effective approach to improve the results of atomic properties for heavy atoms.</jats:p>

<jats:p>The lattice dynamics, elastic properties and the origin of vanished magnetism in equiatomic quaternary Heusler compounds CoMnV<jats:italic>Z</jats:italic> (<jats:italic>Z</jats:italic> = Al, Ga) are investigated by first principle calculations in this work. Due to the similar constituent atoms in CoMnVAl and CoMnVGa compounds, they are both stable in LiMgPdSn-type structure with comparable lattice size, phonon dispersions and electronic structures. Comparatively, we find that CoMnVAl is more structurally stable than CoMnVGa. Meanwhile, the increased covalent bonding component in CoMnVAl enhances its mechanical strength and Vickers hardness, which leads to better comprehensive mechanical properties than those of CoMnVGa. Practically and importantly, structural and chemical compatibilities at the interface make non-magnetic semiconductor CoMnVAl and magnetic topological semimetals Co<jats:sub>2</jats:sub>MnAl/Ga more suitable to be grown in heterostructures. Owing to atomic preferential occupation in CoMnVAl/Ga, the localized atoms Mn occupy C (0.5, 0.5, 0.5) Wyckoff site rather than B (0.25, 0.25, 0.25) and D (0.75, 0.75, 0.75) Wyckoff sites in LiMgPdSn-type structure, which results in symmetric band filling and consequently drives them to be non-magnetic. Correspondingly, by tuning localized atoms Mn to occupy B (0.25, 0.25, 0.25) or/and D (0.75, 0.75, 0.75) Wyckoff sites in off-stoichiometric Co–Mn–V–Al/Ga compounds and keeping the total valence electrons as 24, newly compensated ferrimagnetic compounds are theoretically achieved. We hope that our work will provide more choices for spintronic applications.</jats:p>

<jats:p>Light shift is important and inevitably affects the long-term stability of an atomic clock. In this work, considering two unbalanced branches of the spontaneous decay rate in a three-level system, we studied the frequency shifts of electromagnetically induced transparency (EIT) and coherent population trapping (CPT) clocks operating under the pulse sequence regime by numerically solving the Liouville density matrix equations. The results show that the frequency shifts are larger when the two branches of spontaneous emission rate are not equal compared to the equal case. In addition, in EIT-Ramsey, the effect of the unbalanced branches of the spontaneous decay rate and relaxations of low-energy states on the frequency shift is greater than that of Rabi frequency. In CPT-Ramsey, the relaxations of low-energy states play a dominant role in frequency shift.</jats:p>

<jats:p>Surface plasmon polaritons’ (SPPs’) frequency blue shift is observed in finite-difference time-domain (FDTD) simulation of parallel electron excitation Au bulk structure. Comparing with cold dispersion of SPPs, an obvious frequency blue shift is obtained in low confinement region excitation simulation results. Then, according to SPPs’ transverse attenuation characteristics, the excited frequency mode instead of cold dispersion corresponding frequency mode matches it. Thence, this excited mode is confirmed to be SPPs’ mode. As is well known the lower the frequency, the smaller the confinement factor is and the lower the excitation efficiency, the wider the bandwidth of excited SPPs is. And considering the attenuation in whole structure, the excited surface field contains attenuation signal. In a low confinement factor region, the higher the SPPs’ frequency, the higher the excitation efficiency is, while broadband frequency information obtained in attenuation signal provides high frequency information in stimulation signal. Thence, in the beam–wave interaction, as the signal oscillation time increases, the frequency of the oscillation field gradually increases. Thus, compared with cold dispersion, the frequency of excited SPP is blueshifted This hypothesis is verified by monitoring the time domain signal of excited field in low and high confinement factor regions and comparing them. Then, this frequency-blue shift is confirmed to have commonality of SPPs, which is independent of SPPs’ material and structure. Finally, this frequency-blue shift is confirmed in an attenuated total reflection (ATR) experiment. Owing to frequency dependence of most of SPPs’ devices, such as coherent enhancement radiation and enhancement transmission devices, the frequency-blue shift presented here is of great influence in the SPPs applications.</jats:p>

<jats:p>This paper presents a novel coupled receiver–transmitter metasurface (MS) which is used to realize a high-aperture-efficiency Fabry–Perot resonator antenna. The unit cell of the MS adopts a slot-coupling procedure to realize energy transmission from the receiver patch to the radiator patch. This approach makes it easier to independently control the transmission magnitude and phase. Based on this characteristic, the transmission coefficients of different unit cells on the MS can be optimized by a genetic algorithm. Then, nearly uniform electric amplitude and phase distribution across the aperture field of the antenna are achieved. Therefore, the gain and aperture efficiency of the antenna are improved. A prototype of the optimized antenna is fabricated and measured to validate the design. The measured gain of the fabricated antenna reaches 17.3 dBi with an aperture efficiency of 94.5%. A higher aperture efficiency is obtained with the proposed antenna which has a low profile and simple structure.</jats:p>

<jats:p>Designing and manufacturing cost-effective absorbers that can cover the full-spectrum of solar irradiation is still critically important for solar harvesting. Utilizing control of the lightwave reflection and transmission, metamaterials realize high absorption over a relatively wide bandwidth. Here, a truncated circular cone metasurface (TCCM) composed of alternating multiple layers of titanium (Ti) and silicon dioxide (SiO<jats:sub>2</jats:sub>) is presented. Enabled by the synergetic of surface plasmon resonances and Fabry–Pérot resonances, the TCCM simultaneously achieves high absorptivity (exceed 90%), and absorption broadband covers almost the entire solar irradiation spectrum. In addition, the novel absorber exhibits great photo-thermal property. By exploiting the ultrahigh melting point of Ti and SiO<jats:sub>2</jats:sub>, high-efficiency solar irradiation absorption and heat release have been achieved at 700 °C when the solar concentration ratio is 500 (<jats:italic>i.e.</jats:italic>, incident light intensity at 5 × 10<jats:sup>5</jats:sup> W/m<jats:sup>2</jats:sup>). It is worth noting that the photo-thermal efficiency is almost unchanged when the incident angle increases from 0° to 45°. The outstanding capacity for solar harvesting and light-to-heat reported in this paper suggests that TCCM has great potential in photothermal therapies, solar desalination, and radiative cooling, <jats:italic>etc</jats:italic>.</jats:p>