Two-mode Operator Research Articles

An improved flood forecasting system with cluster based visualization and analyzing using GK-ANFIS and CGDNN

Flooding has been a major causative aimed at social and also economic losses, and also human life’s loss. Flood flow’s accurate forecasting is a vital necessity to decrement the flooding’s risk and is essential to plan and manage the water resources systems, however, due to water flood stage analysis that is an intricate dynamic procedure characterized by temporal and spatial differences it remains to be quite challenging. Aimed at overcoming the challenge, the work has proposed a two-mode operation i.e. Data Visualization (DV) and Data Analysis (DA) for forecasting flood aimed at maintaining an accurate prediction. The main motive of the proposed framework is to forecast the flood in location wise by using the location features. Initially, DV is processed, which is initiated with the data’s quality enhancement for decrementing the error. In aid to fully utilize the database with important data, this work has initiated feature extraction (FE), and thereafter, the features are clustered into a group aimed at evading data misallocation utilizing the levy flight K-means clustering (LF-K-Means Clustering) technique. The clustered data’s visualization is executed utilizing Gaussian Kernel-Adaptive Neuro-Fuzzy Interface System (GK-ANFIS). After that, DA is executed and is initiated with data’s preprocessing followed by flood forecasting (FF) utilizing Conjugate gradient deep neural network (CGDNN) centred on K-Fold cross-validation train test split. Experiential outcomes exhibited that the framework proposed yielded 96.66% prediction accuracy and outshined the existent top-notch method.

Normal product form of two-mode Wigner operator

In the context of normal product, we use the method of the integration within an ordered product (IWOP) of operators to derive three representations of the two-mode Wigner operator: SU(2) symmetric description, SU(1,1) symmetric description and polar coordinate form. We find that two-mode Wigner operator has multiple potential degrees of freedom. As the physical meaning of the selected integral variable changes, Wigner operator shows different symmetries. In particular, in the case of polar coordinates, we reveal the natural connection between the two-mode Wigner operator and the entangled state representation.

New Concept-Based Six-Wheels Rocker-Bogie Robot: Design and analysis

In the last decay, various missions have conducted to explore the science behind the space phenomenon. An autonomous robot is essential for space exploration, such as Moon, Mars, and Saturn. This robot-like rover plays a vital role in collecting data and sample on the planet’s unplanned surface. This paper presents the necessary kinematic and dynamic stability of rocker-bogie on an uneven surface. The concept of a designed rocker-bogie robot ensures a new technique for optimum stability conditions of rocker-bogie and self-adaptability using a link mechanism during high-speed mode operation. It consists of a two-mode operations system with six wheels. The rocker-bogie wheels are aligned with the bar link mechanism. The two-mode operation system mechanism of rocker-bogie is simulated. Further on, the prototype of rocker-bogie is designed and fabricated by considering optimum fittest data from the simulation. The performance evaluation of the developed prototype and results is then compared with simulation aiming to strengthen vehicle stability. The newness of this present investigation are: - (i) the improvement of travel rate of rocker-bogie in case of planner surface by switching the front span from its original configure, (ii) dynamical suspension having two operational, (iii) expansion of supported polygon for increasing the travel rate in case of plane terrain, (iv) self-switching to its original configuration at low speed while it faces rough terrain.

Broadband complex two-mode quadratures for quantum optics

In their seminal paper, Caves and Schumaker presented a new formalism for quantum optics, intended to serve as a building block for describing two-photon processes, in terms of new, generalized qudratures. The important, revolutionary concept in their formalism was that it was fundamentally two-mode, i.e. the related observables could not be attributed to any single one of the comprising modes, but rather to a generalized complex quadrature that could only be attributed to both of them. Here, we propose a subtle, but fundamentally meaningful modification to their important work. Unlike the above proposal, we deliberately choose a frequency-agnostic definition of the two-mode quadrature, that we motivate on physical grounds. This simple modification has far-reaching implications to the formalism – the real and imaginary parts of the quadratures now coincide with the famous EPR variables, and our two-mode operators transform trivially under two-mode and single-mode squeezing operations. Their quadratic forms, which we call the “quadrature powers” are shown to succinctly generate the SU(1, 1) algebra of squeezing Hamiltonians, and correspond directly to important, broadband physical observables, that have been directly measured in experiment and are explicitly related to properties like squeezing and entanglement. This new point of view gives a fresh perspective on two-mode processes that is completely agnostic to the bandwidth, and reveals intriguing new ways for understanding and measuring broadband two-mode squeezing.

Coherence dynamics induced by attenuation and amplification Gaussian channels

Quantum Gaussian channels play a key role in quantum information theory. In particular, the attenuation and amplification channels are useful to describe noise and decoherence effects on continuous variables systems. They are directly associated to the beam splitter and two-mode squeezing operations, which have operational relevance in quantum protocols with bosonic models. An important property of these channels is that they are Gaussian completely positive maps and the action on a general input state depends on the parameters characterizing the channels. In this work, we study the coherence dynamics introduced by these channels on input Gaussian states. We derive explicit expressions for the coherence depending on the parameters describing the channels. By assuming a displaced thermal state with initial coherence as input state, for the attenuation case it is observed a revival of the coherence as a function of the transmissivity coefficient, whereas for the amplification channel the coherence reaches asymptotic values depending on the gain coefficient. Further, we obtain the entropy production for these class of operations, showing that it can be reduced by controlling the parameters involved. We write a simple expression for computing the entropy production due to the coherence for both channels. This can be useful to simulate many processes in quantum thermodynamics, as finite-time driving on bosonic modes.

On Trajectory Design for Intruder Detection in Wireless Mobile Sensor Networks

We address the problem of detecting the invasion of an intruder into a region of interest (ROI) which is monitored by a distributed bandwidth-constrained wireless mobile sensor network (WMSN). We design periodic trajectories for the mobile sensor nodes (MSNs) such that high detection probabilities are obtained while maintaining the MSNs' energy consumption low. To reduce the transmission and processing burden on the MSNs, we propose an operation algorithm based on two modes, surveying mode and confirmation mode. In the former, to efficiently detect the intruder while using little mechanical energy, we optimize the surveying path such that the sensed area is maximized. During this mode, each MSN performs local detection and switches to the confirmation mode if and only if the intruder is suspected to be present. In the confirmation mode, each MSN collects further measurements over a predefined duration to reduce the detection uncertainly. A binary local hypothesis testing is performed at each MSN and only positive test statistics are transmitted to the FC where the ultimate decision is taken. Simulations results show the merits of the proposed two-mode operation algorithm in terms of detection performance and energy efficiency.

Towards Energy-Autonomous Unmanned Aerial System: A Bionic Approach on Solar-Electric, Multi-Vehicle Aerial Platforms for Waterborne Operations

An alternative approach on energy-autonomous unmanned aerial systems is proposed: By a collaborative, multi-vehicle architecture, the infinite flight-concept of High-Altitude Solar-Powered Vehicles is replaced by a bionic inspired two-mode operation. Mission tasks are conducted with full functionalities by active vehicles, while the remaining inactive vehicles rest at a sleep-like phase of minimum power consumption, increasing the efficiency of energy regeneration. As an exemplary case, a solar-electric powered system of waterborne, fixed-wing vehicles is studied. Assuming a search-and-detect mission scenario, probable vehicle and system designs are investigated. Impact of seasonal and meteorological availability of solar insolation, vehicle operation scheme, sensor and datalink properties on system performance are evaluated by a multi-agent-based mission simulation. Optimization potentials, as well as learnings on system architecture, vehicle design and mission scenario are presented.

Nonlinear optical tomography of q-deformed entangled pair coherent states

We introduce entangled pair coherent states of a noncommutative harmonic oscillator operators associated with a q-deformed oscillator algebra. The definition of two-mode q-deformed operator and the decomposition of its eigenstates in terms of the q-deformed Fock states are obtained. The general solution of the recurrence relation of the first nondeformed quadrature is obtained. The asymptotic behavior of the general solution is studied, a complete expansion is derived, and also representations of the general solution in terms of the Gauss hypergeometric function are given. Also, we prove that the general solution is related to Meixner-Pollaczek orthogonal polynomial and calculate the weight function. The photons number distribution, the second order correlation function and the optical tomogram of the entangled pair coherent states are discussed. The recurrence relation for the first q-deformed quadrature is inferred. We evaluate the eigenstate of the q-deformed quadrature operator and give a numerical study for the optical tomogram of the q-deformed of the entangled pair coherent states. Finally, we show the change of the parameters in the entangled pair coherent states that connected with physical quantities and explain how they affect the format of optimal tomography.

Computer modeling of a biharmonic oscillator

In this work computer modeling of a two-mode Colpitts oscillator operating in the phase locking of two modes was carried out. Modeling of an oscillator operating modes and the experiment allow to draw a conclusion about possibility of phase noise reduction in a stationary synchronous biharmonic mode that can be used in the frequency stabilization task.

Projection operators for asymmetric two-mode coherent states and two-mode Fock states

Operators play an important role in the formalism of quantum mechanics. By means of the technique of integration within an ordered product of operators and Dirac notation, we analytically prove that a new kind of asymmetric two-mode projection integral operator and another asymmetric two-mode Fock state projection summation operator are equal to the same Hermitian operator. For such Hermitian operator, we also rigorously demonstrate it corresponds to a parity measurement of a two-mode quantum state after passing through a beam splitter. The method used in this work provides a good exercise in quantum mechanics at the graduate level.

Development in Phase Space Quantum Mechancis for Constructing Different Masses’ Entangled State Representation

For developing the phase space quantum mechanics we explore how to construct different masses’ entangled state representation with the use of tthe Weyl-Wigner correspondence. We shall adopt a new approach, which uses the Radon transform of two-mode Wigner operator in normally ordering form to realize our goal. As an application of the entangled state representation the new normally ordered generalized squeezing operator is derived. The technique of integration within ordered product of operators is fully used.

A Novel THz Forward and Backward Wave Two-Mode Band-Edge Oscillator

In this article, a novel two-mode operation concept for the THz oscillator with the folded waveguide is proposed. To demonstrate this concept, a two mode 4π band-edge oscillator has been simulated and fabricated. The simulation predicted that the designed oscillator was capable of delivering maximal output power of over 2 W at 301.7–303 GHz for both forward and backward operation mode. On the other hand, the testing data showed that the first prototype of the two-mode oscillator was able to produce output power over 1 W at about 305.6 GHz (voltage 23.04 kV) and 1.51 W at 308.8 GHz (voltage 24.33 kV), for forward and backward operation mode, respectively, with a 5–7 GHz frequency shift compared to the simulation. The findings demonstrate the correctness of the proposed two-mode concept for developing novel two-mode band-edge oscillators. There exist some inconsistencies between the testing and simulation, which will be discussed in the article. It is believed that the proposed two-mode concept is useful for the exploration of other novel two-mode band-edge oscillators, such as compact, high-power THz radiation sources for potential applications.

Optical complex integration-transform for deriving complex fractional squeezing operator**Project supported by the National Natural Science Foundation of China (Grant No. 11775208) and Key Projects of Huainan Normal University, China (Grant No. 2019XJZD04).

We find a new complex integration-transform which can establish a new relationship between a two-mode operator’s matrix element in the entangled state representation and its Wigner function. This integration keeps modulus invariant and therefore invertible. Based on this and the Weyl–Wigner correspondence theory, we find a two-mode operator which is responsible for complex fractional squeezing transformation. The entangled state representation and the Weyl ordering form of the two-mode Wigner operator are fully used in our derivation which brings convenience.

Generation of various classes of entangled states in a two-mode Bose–Einstein condensate under the influence of interatom collisions

In this paper, we generate some new classes of entangled states of a bimodal Bose–Einstein condensate (BEC), a pair of tunnel-coupled BEC, in the presence of two- and three-body elastic as well as mode-exchange collisions. The Hamiltonian of the considered system is very complicated, moreover, it can be fortunately transformed into a simple form using a two-mode displacement operator. After introducing the general form of the time evolved state, various classes of entangled states are generated. Indeed, the influence of different orders of tunneling strengths on the generated entangled states has been studied. Depending on the tunneling strength constants, two-, three- and four-partite entangled states are generated, all of which are superposition states of macroscopic number of BEC atoms. Considering three-particle collision dramatically changes the generated entangled states. Moreover, in particular cases, the resulted states are non-entangled. Also, we show that tunneling and collisional interactions can be manipulated to generate a pair of atomic entangled coherent states (quasi-Bell states). In addition, it is observed that the degree of entanglement for two-partite entangled states can be tuned via the number of BEC atoms, i.e. the corresponding concurrences tend to their maximum value by increasing the atoms in both modes of system.

Enhancing entanglement of entangled coherent states via a f-deformed photon-addition operation

In this paper, we introduce a new kind of photon-added entangled coherent states (PA-ECSs), by performing repeatedly a f-deformed photon-addition (DPA) operation, $ A^{\dagger}= f(\hat{n}) a^{\dagger}$, on each mode of the entangled coherent states (ECSs), $ \vert\Psi_{\pm}(\alpha)\rangle$. By choosing a particular deformation function $ f(\hat{n})$, we study how the entanglement properties can be enhanced by DPA operation. As a result, we show that both the single and two-mode DPA operation can be used to improve the entanglement of $ \vert\Psi_{+} (\alpha)\rangle$, where the effects of improvement by two-mode DPA operation are more prominent than those by single-mode DPA operation, in any amplitude regime. Moreover, our results show there exists a family of coherent amplitudes $| \alpha |$ such that the two-mode DPA operation preserves the maximal entanglement of the odd ECSs $ \vert\Psi_{-}(\alpha)\rangle$, where the non-deformed photon-addition operation $ a^{\dagger}$ suppresses the entanglement amount. Finally, a theoretical scheme for the physical generation of the introduced states based on a Jaynes-Cummings model with intensity-dependent couplings is proposed.

Multiple-Photon-Added and -Subtracted Two-Mode Binomial States: Nonclassicality and Entanglement**Supported by the National Natural Science Foundation of China under Grant No. 11347026, the Natural Science Foundation of Shandong Province under Grant Nos. ZR2016AM03 and ZR2017MA011

We theoretically analyze the nonclassicality and entanglement of two new non-Gaussian entangled states generated by applying multiple-photon addition and subtraction to a two-mode binomial state. The nonclassical properties are investigated in terms of the partial negativity of the Wigner functions, whose results show that their nonclassicality can be enhanced via one-mode even-number photon operations and two-mode symmetrical operations for the initial two-mode binomial state. We also find that there exists some enhancement in the entanglement properties in certain parameter ranges via one-mode photon-addition and two-mode symmetrical operations.

Dual-Band Coaperture Antenna Based on a Single-Layer Mode Composite Transmission Line

A novel coaperture antenna based on the concept of mode composite transmission line and named mode composite antenna (MCA) is proposed in this communication. The MCA combines the structure of a monopole antenna and a substrate integrated waveguide (SIW) slot antenna to form a new coaperture antenna. Because of the structure sharing characteristic in MCA, it can reduce the size of the antenna. The MCA serves as the monopole antenna supporting the surface current on the antenna patch in its low-band operation. In its high-band operation, the SIW will support TE10 to excite the slot array. The two-mode operation has high isolation which makes the MCA a promising candidate for multiband application. The measured and simulated results agreed well and validated the feasibility of the MCA.

Two-mode Hadamard vacuum state and its properties

We investigate nonclassical properties of the quantum state generated by operating a two-mode Hadamard operator on the vacuum state. It is found that the scale length parameter of this new state plays an important role in squeezing. The anti-bunching effect, entanglement, and nonlocality are also derived analytically.

The Influence of Wide-Band Frequency Modulation on the Competition of Orthogonally Polarized Modes in a Two-Mode Laser

Competitive interaction of orthogonally polarized modes in a two-mode laser operating in a regime of wide-band frequency modulation has been numerically simulated. This modulation was implemented by means of the corresponding variation of the laser cavity length. Parameters of the active medium adopted in the numerical model were characteristic of He–Ne lasers with an inhomogeneously broadened gain line. It is established that negative consequences of the mode competition can be significantly reduced at certain values of the modulation frequency and frequency deviation.

Investigation of the Two-Mode Operation of Avalanche Photodiodes in the Registration of Optical Radiation

The possibility of the simultaneous operation of avalanche photodiodes in the photon-counting and current modes is shown. The double-mode operation is provided at a constant supply voltage of an avalanche photodiode that exceeds the breakdown voltage of its p–n junction. The probability of the formation of microplasma pulses as a function of the intensity of optical radiation and the supply voltage of the avalanche photodiode is estimated for the considered operating mode.