Catálogo de publicaciones - revistas

<jats:title>Abstract</jats:title> <jats:p>We report on a method to achieve multiple microscopic particles trapping and transverse manipulation using a size-tunable Bessel beam generated by cross-phase modulation (XPM) based on the thermal nonlinear optical effect. The results demonstrates that multiple polystyrene particles can be stably trapped simultaneously, and the number of the trapped particles can be controlled by varying the trapping beam power. In addition, the trapped particles can be manipulated laterally with micron-level precision by changing the size of <jats:italic>J</jats:italic> <jats:sub>0</jats:sub> Bessel beam. This work provides a simple but efficient way to trap and manipulate multiple particles simultaneously, which would be of potential in many applications such as cell sorting and transportation.</jats:p>

<jats:title>Abstract</jats:title> <jats:p>Due to the continuous emergence of molecular and cluster devices or systems, the relationship between the plasmonic properties of multiple clusters and the molecular interactions and properties of a single cluster or molecule has become increasingly important. A hybrid phenomenon similar to plasmonic nanoparticle hybridization exists between two molecules with plasmon excitation modes. We use linear-response time-dependent density functional theory (LRTDDFT), real-time propagation time-dependent density functional theory (RT-TDDFT), the plasmonicity index (PI) and transition contribution maps (TCMs) to identify the plasmon excitation modes for the linear polyenes octatetraene with -<jats:italic>OH</jats:italic> and -<jats:italic>NH</jats:italic> <jats:sub>2</jats:sub> groups and analyze the hybridization characteristics using charge transitions. The results show that molecular plasmon hybridization exists when the two molecules are coupled. The TCM analysis shows that the plasmon modes and hybridization are the results of collective and single-particle excitation. The plasmon mode is stronger, and the individual properties of the molecules are maintained after coupling when there is extra charge depose in the molecules because the electrons are moving in the molecules. This study provides new insights into the molecular plasmon hybridization of coupled molecules.</jats:p>

<jats:title>Abstract</jats:title> <jats:p>Optical systems offer rich modulation in light propagation, but sufficient quantitative descriptions lack when highly complex structures are considered since practical structures contain defects or imperfections. Here, we utilize a method combining a data-fitting method and a time-resolved system to describe light propagation near the band edges in one-dimensional structures. Calculations after optimization of the method show little deviation to the measurements.</jats:p>

<jats:title>Abstract</jats:title> <jats:p>In this work, we have demonstrated antimonene as a saturable absorber to generate ultrafast mode-locked and Q-switched laser at a 2-micron wavelength region. The two antimonene-based SAs were prepared and inserted separately in a thulium-holmium doped fiber laser (THDFL) to produce the pulsed lasers. Antimonene was coated onto the tapered fiber to generate soliton mode-locked pulses and in thin-film form for the generation of Q-switched pulses. The modelocking was stable within the pump power of 267 to 511 mW, and the laser operated at the center wavelength of 1897.4 nm. The mode-locked laser had a pulse width of 1.3 ps and a repetition rate of 12.6 MHz, with a signal-to-noise ratio (SNR) of 64 dB. The Q-switched laser operation was stable at the wavelength of 1890.1 nm within the pump power of 312 to 381 mW. With the increase in pump power from 312 mW to 381 mW, the repetition rate increased to a maximum of 56.63 kHz and the pulse width decreased to a minimum value of 2.85 μs. A wide range tunability of Q-switched laser was also realized within the wavelength of 1882 to 1936 nm.</jats:p>

<jats:title>Abstract</jats:title> <jats:p>We study modulational instability of a resonantly polariton condensate in a discrete lattice. Employing a discrete gain-saturation model, we derive the dispersion relation for the modulational instability by means of the linear-stability analysis. Effects of the pumping strength, the nonlinearity, the strength of the detuning and the coupling strength on the MI are investigated. We find that the interplay between these parameters will dramatically change the modulational instability condition. We believe that the predicted results in this work can be useful for the future possible experiment of exciton-polariton condensate in the lattices.</jats:p>

<jats:title>Abstract</jats:title> <jats:p>Single-electron spins in quantum dots are the leading platform for qubits, while magnons in solids are one of the emerging candidates for quantum technologies. How to manipulate a composite system composed of both systems is an outstanding challenge. Here, we use spin-charge hybridization to effectively couple the single-electron spin state in quantum dots to the cavity and further to the magnons. Through this coupling, quantum dots can entangle and detect magnon states. The detection efficiency can reach 0.94 in a realistic experimental situation. We also demonstrate the electrical tunability of the scheme for various parameters. These results pave a practical pathway for applications of composite systems based on quantum dots and magnons.</jats:p>

<jats:title>Abstract</jats:title> <jats:p>Using improved particle swarm optimization algorithm(IPSO) to drive transfer matrix method(TMM), a nonreciprocal absorber with an ultrawide absorption bandwidth and angular insensitivity(UBAI) is realized in the plasma-embedded photonic crystals(PPCs) arranged by the structure composed of periodic sequence and the quasi-periodic sequence on a normalized scale. Effective dielectric function, which determines absorption of plasma, is subject to basic parameters of plasma, making absorption of proposed absorber easily be modulated by basic parameters of plasma. Compared with different quasi-periodic sequences, Octonacci sequence fully wins both in relative bandwidth and absolute bandwidth. Under further optimization using IPSO, fourteen parameters set to be optimized, absorption characteristics of proposed structure in different amounts of layers of smallest structure unit <jats:italic>N</jats:italic> are shown and discussed. IPSO is also used to address angular insensitive nonreciprocal ultrawide bandwidth absorption, and optimized result shows excellent unidirectional absorbability and angular insensitivity of proposed structure. The impacts of sequence number of quasi-periodic sequence <jats:italic>M</jats:italic>, collision frequency of plasma<jats:sub>1</jats:sub> <jats:italic>ν</jats:italic> <jats:sub>1</jats:sub> to absorption in angle domain and frequency domain are investigated. Additionally, the impedance match theory and the interference field theory are introduced to express what the algorithm works out.</jats:p>

<jats:title>Abstract</jats:title> <jats:p>The magnetic skyrmion transport driven by pure voltage-induced strain gradient is proposed and studied via micromagnetic simulation. Through combining the skyrmion with multiferroic heterojunction, a voltage-induced uniaxial strain gradient is adjusted to move skyrmions. In the system, a pair of short-circuited trapezoidal top electrodes can generate the symmetric strain. Due to the symmetry of strain, the magnetic skyrmion can be driven with a linear motion in the middle of the nanostrip without deviation. We calculate the strain distribution generated by the trapezoidal top electrodes pair, and further investigate the influence of the strain intensity as well as the strain gradient on the skyrmion velocity. Our findings provide a stable and low-energy regulation method for skyrmion transport.</jats:p>

<jats:title>Abstract</jats:title> <jats:p>We have derived the analytical formulas for the Kelvin–Helmholtz instability (KHI) of two superposed finite-thickness fluid layers with the magnetic field effect into consideration. The linear growth rate of KHI will be reduced when the thickness of the fluid with large density is decreased or the thickness of fluid with small density is increased. When the thickness and the magnetic field act together on the KHI, the effect of thickness is more obvious when the magnetic field intensity is weak. The magnetic field transition layer destabilizes (enforces) the KHI, especially in the case of small thickness of the magnetic field transition layer. When considering the effect of magnetic field, the linear growth rate of KHI always decreases after reaching the maximum with the increase of total thickness. The stronger the magnetic field intensity is, the more obvious the growth rate decreases with the total thickness. Thus, it should be included in applications where the effect of fluid thickness on the KHI can not be ignored, such as in double-cone ignition scheme for inertial confinement fusion.</jats:p>

<jats:title>Abstract</jats:title> <jats:p>Explicit visualization of different components of surface plasmon polaritons (SPPs) propagating at dielectric/metal interfaces is crucial in offering chances for the detailed design and control of the functionalities of plasmonic nanodevices in the future. Here, we reported independent imaging of the vertical and horizontal components of SPPs launched from a rectangular trench in the gold film by a 400 nm laser-assisted near-infrared (NIR) femtosecond laser time-resolved photoemission electron microscopy (TR-PEEM). The experiments demonstrate that distinct imaging of the different components of the SPPs field can be easily achieved by introducing the 400 nm laser. It can circumvent the risk of sample damage and the information loss of the excited SPPs field that is generally confronted in the usual NIR laser TR-PEEM scheme. The underlying mechanism for realizing distinct imaging of the different components of the SPPs field with two-color PEEM is revealed via measuring the double logarithmic dependence of photoemission yield with the 800 nm and 400 nm pulse power of different polarization. Moreover, it is found that the PEEM image quality of the vertical and horizontal components of the SPPs field is nearly independent of the 400 nm pulse polarization. These results pave a way for SPPs-based applications and offer a possible solution for drawing a space-time field of SPPs in three dimensions.</jats:p>