Dynamics of matter-wave solitons in three-component Bose-Einstein condensates with time-modulated interactions and gain or loss effect

The gain or loss effect on the dynamics of the matter-wave solitons in three-component Bose-Einstein condensates with time-modulated interactions trapped in parabolic external potentials are investigated analytically. Some exact matter-wave soliton solutions to the three-coupled Gross-Pitaevskii equation describing the three-component Bose-Einstein condensates are constructed by similarity transformation. The dynamical properties of the matter-wave solitons are analyzed graphically, and the effects of the gain or loss parameter and the frequency of the external potentials on the matter-wave solitons are explored. It is shown that the gain coefficient makes the atom condensate to absorb energy from the background, while the loss coefficient brings about the collapse of the condensate.

Cascaded PT-Symmetric Artificial Sheets: Multimodal Manipulation of Self-Dual Emitter-Absorber Singularities, and Unidirectional and Bidirectional Reflectionless Transparencies

We herein introduce cascaded parity-time (PT)-symmetric artificial sheets (e.g., metasurfaces or frequency selective surfaces) that may exhibit multiple higher-order laser-absorber modes and bidirectional reflectionless transmission resonances within the PT-broken phase, as well as a unidirectional reflectionless transmission resonance associated with the exceptional point (EP). We derive the explicit expressions of the gain-loss parameter required for obtaining these modes and their intriguing physical properties. By exploiting the cascaded PT structures, the gain-loss threshold for the self-dual laser-absorber operation can be remarkably lowered, while the EP remains unaltered. We further study interferometric sensing based on such a multimodal laser-absorber and demonstrate that its sensitivity could be unprecedentedly high and proportional to the number of metasurfaces along the light propagation direction.

Solitons in a PT -symmetric grating-assisted co-directional coupler

We explore a co-directional coupling arrangement between two waveguides mediated by a PT-symmetric sinusoidal grating characterized by an index-modulation parameter κ and a gain/loss parameter g. We show that the device supports soliton-like solutions for both the PT -conserving regime g < κ and the PT -broken regime g > κ. In the first case the coupler exhibits a gap in wave-number k and the solitons can be regarded as an extension of a previous solution found for pure index modulation. In the second case the coupler exhibits a gap in frequency ω and the solutions are entirely new.

2x2 Grid Array Design with E-shaped Microstrip Elements

The paper proposes a work of four element in a 2×2 grid fashioned with E-shaped microstrip patch antenna with corporate fed .The paper compares the proposed design with four elements with a single element and a 2 element array design.All the three antenna designs use E shaped microstrip patch as an element. The design of the grid is achieved through the design of a single element, the design of a 1×2 array and finally the design of the 2×2 grid on an FR4 epoxy substrate of thickness 1.5 mm. A corporate feed network of microstrip lines is used to excite the array. The performance of each stage is studied in terms of the return loss parameter, the far field gain, and the beam-widths are observed in each case from simulation results. The resonant frequency in each case is 3.8 GHz. Through comparision of simulation results the paper shows that as the number of elements is increased, the beam-width reduces. In other words, the directivity is increased. Further, it is also observed that the gain and bandwidth is the minimum for the single patch, followed by that of the 1×2 array and the maximum for the 2×2 grid. Thus,it is ssen that the proposed four element antenna with corporate feeding performs better as compared to antennas with either only single patch element or two element array. The construction of the grid leads to increase in gain, bandwidth and directivity of the antenna.

Non-Hermitian Electronics Multipods of Electromagnetically Induced Transparency (EIT) and Absorption (EIA)

We study a non-Hermitian electronic dimers system based on an imaginary resistor (Z) in a (N+2) level atomic multi-pod configuration. Non-Hermitian systems depend on a gain/loss parameter and are specifically marked by a degeneracy exhibited at an exceptional point (EP) separating different phases of complex modes dynamics. Interestingly, the structural characterization and the dispersive properties reveal a broad range of strong coupling where the interplay between the control and the probe field induce a simultaneous EIT, EIA and ATS. Here, by identifying the underlying physical mechanisms, we show that multiple windows of transparency can be strongly enhanced by the incorporation of several dimers in the multipod network. On the other hand, if the pumping field is resonant in the weak regime, multiple EIT and EIA windows result in the number of dimers. Remarkably, the proposed system embedded a multiple coupling mechanism whose modulation induces a couplingless point whereby the energy cross. At this point EIT and related phenomena vanish.

Designing of a 2x2 E-shaped Microstrip Patch Grid Antenna

In this work, a 2×2 grid of E-shaped patch antennas is proposed. The design of the grid is achieved through the design of a single element, the design of a 1×2 array and finally the design of the 2×2 grid on an FR4 epoxy substrate of thickness 1.5 mm. A corporate feed network of microstrip lines is used to excite the array. The performance of each stage is studied in terms of the return loss parameter, the far field gain, and the beam-widths are observed in each case from simulation results. The resonant frequency in each case is 3.8 GHz. It is observed that as the number of elements is increased, the beam-width reduces. In other words, the directivity is increased. Further, it is also observed that the gain and bandwidth is the minimum for the single patch, followed by that of the 1×2 array and the maximum for the 2×2 grid. Thus, the construction of the grid leads to increase in gain, bandwidth and directivity of the antenna.

Quality of Service Packet Loss Pada Sistem Home Monitoring Water Flow Berbasis Internet of Things

Perilaku boros air bersih menyebabkan semakin banyak orang yang kehilangan akses terhadap air bersih. Penggunaan air di dalam rumah tangga selama ini masih sangat sulit untuk dilakukan pengelolaan dalam penggunaan air secara efektif. Kelangkaan air bersih adalah situasi saat terjadinya kekurangan air untuk memenuhi kebutuhan manusia. Penelitian ini menmbangun sistem Home Water Flow Monitoring (HEROIG) berbasis Internet of Things (IoT) untuk melakukan monitoring dan controlling penggunaan air pada rumah. Perangkat keras menggunakan NodeMCU sebagai mikrokontroler serta mengirimkan hasil sensing debit air oleh sensor water flow yang akan dikirimkan ke cloud server. Pengontrolan dapat dilakukan melalui aplikasi android HEROIG yang telah dibuat dan terintegrasi dengan sistem IoT yang harus bekerja dalam koneksi jaringan yang baik. Pengujian kualitas koneksi jaringan atau Quality of Services (QoS) khususnya packet loss menggunakan dua parameter yaitu dari waktu dan jarak. Hasil pengujian packet loss parameter waktu dengan pengujian enam detik sekali dalam waktu satu menit memiliki nilai rata-rata packet loss 1,13%, kemudian untuk pengujian parameter jarak dengan selisih setiap jarak adalah empat meter memiliki nilai rata-rata packet loss 0,15%. Hasil pengujian tersebut menunjukan kualitas pengiriman data sensor ke cloud server memiliki parameter QoS packet loss kategori sangat baik, karena memiliki nilai packet loss <3%.

The Fractional Nonlinear PT Dimer

We examine a fractional Discrete Nonlinear Schrodinger dimer, where the usual first-order derivative of the time evolution is replaced by a non integer-order derivative. The dimer is nonlinear (Kerr) and PT-symmetric, and we examine the exchange dynamics between both sites. By means of the Laplace transformation technique, the linear PT dimer is solved in closed form in terms of Mittag-Leffler functions, while for the nonlinear regime, we resort to numerical computations using the direct explicit Grunwald algorithm. In general, the main effect of the fractional derivative is the onset of a monotonically decreasing time envelope for the amplitude of the oscillatory exchange. In the presence of PT symmetry, the dynamics shows damped oscillations for small gain/loss in both sites, while at higher gain/loss parameter values, the amplitudes of both sites grows unbounded. In the presence of nonlinearity, selftrapping is still possible although the trapped fraction decreases as the nonlinearity is increased past threshold, in marked contrast with the standard case.

Excitation Analysis of Transverse Electric Mode Rectangular Waveguide

A waveguide is a transmission medium in the form of a pipe and is made from a single conductor. A waveguide has the function of delivering electromagnetic waves with a frequency of 300 MHz - 300 GHz and is able to direct the waves in a particular direction. In its development, a waveguide can be used as a filter. A filter consists of several circuits designed to pass signals that are generated at a specific frequency and attenuate undesired signals. One type of filter that can pass a signal in a particular frequency range and block signals that are not included in that frequency range is a bandpass filter. In this article, we study a rationing analysis on rectangular waveguide using TEmn mode followed by an implementation of a bandpass filter in the frequency range of 3.3-3.5 GHz for S-Band Wireless Broadband and Fixed Satellite. The observation process is done by shifting the position of the connector (power supply) as much as five times the shift to get the results as desired. Based on the analysis of the simulation process using Ansoft HFSS software, it is observed that the optimized results of the rectangular waveguide mode TE10 were obtained at a distance between connectors of 30 mm with a cut-off frequency of 3.3 GHz, the value of the return loss parameter of -34.442 dB and an insertion loss of -0.039 dB. Whereas, the optimized TE20 mode can be obtained at a distance of 70 mm between connectors, with a cut-off frequency of 3.5 GHz, the value of the return loss parameter of -28.718 dB and an insertion loss of -0.045. The measurement of TE10 mode in our Vector Network Analyzer (VNA) shows a cut-off frequency of 3.2 GHz, with a value of the return loss of -18.73 dB and an insertion loss of -2.70 dB. Meanwhile, a measurement of TE20 mode results in a cut-off frequency of 3.2 GHz, with a value of the return loss of -5.89 dB and an insertion loss of -4.31 dB.