arXiv subjects

Zhan-Ying Yang

Publications and source records attributed to Zhan-Ying Yang.

At least 37 records · Page 2Linked to original sources

arXiv2018

Growth rate of modulation instability driven by superregular breathers

We report an exact link between Zakharov-Gelash super-regular (SR) breathers (formed by a pair of quasi-Akhmediev breathers) with interesting different nonlinear propagation characteristics and modulation instability (MI). This shows that the absolute difference of group velocities of SR breathers coincides exactly with the linear MI growth rate. This link holds for a series of nonlinear Schrödinger equations with infinite-order terms. For the particular case of SR breathers with opposite group velocities, the growth rate of SR breathers is consistent with that of each quasi-Akhmediev breather along the propagation direction. Numerical simulations reveal the robustness of different SR breathers generated from various non-ideal single and multiple initial excitations. Our results provide insight into the MI nature described by SR breathers and could be helpful for controllable SR breather excitations in related nonlinear systems.

nlin.PS↗

arXiv2018

Breathers and solitons on two different backgrounds in a generalized coupled Hirota system with four wave mixing

We study breathers and solitons on different backgrounds in optical fiber system, which is governed by generalized coupled Hirota equations with four wave mixing effect. On plane wave background, a transformation between different types of solitons is discovered. Then, on periodic wave background, we find breather-like nonlinear localized waves of which formation mechanism are related to the energy conversion between two components. The energy conversion results from four wave mixing. Furthermore, we prove that this energy conversion is controlled by amplitude and period of backgrounds. Finally, solitons on periodic wave background are also exhibited. These results would enrich our knowledge of nonlinear localized waves' excitation in coupled system with four wave mixing effect.

nlin.PS↗

arXiv2018

Atomic Bright Soliton Interferometry

The properties of nonlinear interference pattern between atomic bright solitons are characterized analytically, with the aid of exact solutions of dynamical equation in mean-field approximation. It is shown that relative velocity, relative phase, and nonlinear interaction strength can be measured from the interference pattern. The nonlinear interference properties are proposed to design atomic soliton interferometry in Bose-Einstein condensate. As an example, we apply them to measure gravity acceleration in a ultra-cold atom systems with a high precision degree. The results are also meaningful for precise measurements in optical fiber, water wave tank, plasma, and other nonlinear systems.

cond-mat.quant-gas↗

arXiv2018

Femtosecond Optical Superregular Breathers

Superregular (SR) breathers are nonlinear wave structures formed by a unique nonlinear superposition of pairs of quasi-Akhmediev breathers. They describe a complete scenario of modulation instability that develops from localized small perturbations as well as an unusual quasiannihilation of breather collision. Here, we demonstrate that femtosecond optical SR breathers in optical fibers exhibit intriguing half-transition and full-suppression states, which are absent in the picosecond regime governed by the standard nonlinear Schrödinger equation. In particular, the full-suppression mode, which is strictly associated with the regime of vanishing growth rate of modulation instability, reveals a crucial \textit{non-amplifying} nonlinear dynamics of localized small perturbations. We numerically confirm the robustness of such different SR modes excited from ideal and nonideal initial states in both integrable and nonintegrable cases.

nlin.PS↗

arXiv2017

Coherence transformations in single qubit systems

We investigate the single qubit transformations under several typical coherence-free operations, such as, incoherent operation (IO), strictly incoherent operation (SIO), physically incoherent operation (PIO), and coherence preserving operation (CPO). Quantitative connection has been built between IO and SIO in single qubit systems. Moreover, these coherence-free operations have a clear hierarchical relationship in single qubit systems: CPO $\subset$ PIO $\subset$ SIO=IO. A new and explicit proof for the necessary and sufficient condition of single qubit transformation via IO or SIO has been provided, which indicates that SIO with only two Kraus operators are enough to realize this transformation. The transformation regions of single qubits via CPO and PIO are also given. Our method provides a geometric illustration to analyze single qubit coherence transformations by introducing the Bloch sphere depiction of the transformation regions, and tells us how to construct the corresponding coherence-free operations.

quant-ph↗

arXiv2017

Vector rogue waves on a double-plane wave background

We study rogue wave excitation dynamics on a double-plane wave background through deriving rogue wave solution on the background. The results indicate that rogue wave still can be excited successfully from resonant perturbations with the two plane wave backgrounds. The obtained vector rogue wave can be decomposed to two rogue waves located on the two backgrounds separately. This enables us to investigate the superpositions of two of the three well-known fundamental rogue wave patterns, mainly including eye-shaped, anti-eye-shaped, and four-petaled one. The explicit conditions for different possible superpositions are clarified by a phase diagram for rogue wave pattern on each plane wave background. The detail analysis indicate that the rogue wave admits many different profiles, in contrast to the ones reported before. The studies can be extended directly to investigate other localized waves on double-plane wave background and even more plane waves involved cases.

nlin.PS↗

arXiv2017

Coherence depletion in the Grover quantum search algorithm

We investigate the role of quantum coherence depletion (QCD) in Grover search algorithm (GA) by using several typical measures of quantum coherence and quantum correlations. By using the relative entropy of coherence measure ($\mathcal{C}_r$), we show that the success probability depends on the QCD. The same phenomenon is also found by using the $l_1$ norm of coherence measure ($\mathcal{C}_{l_1}$). In the limit case, the cost performance is defined to characterize the behavior about QCD in enhancing the success probability of GA, which is only related to the number of searcher items and the scale of database, no matter using $\mathcal{C}_r$ or $\mathcal{C}_{l_1}$. In generalized Grover search algorithm (GGA), the QCD for a class of states increases with the required optimal measurement time. In comparison, the quantification of other quantum correlations in GA, such as pairwise entanglement, multipartite entanglement, pairwise discord and genuine multipartite discord, cannot be directly related to the success probability or the optimal measurement time. Additionally, we do not detect pairwise nonlocality or genuine tripartite nonlocality in GA since Clauser-Horne-Shimony-Holt inequality and Svetlichny's inequality are not violated.

quant-ph↗

arXiv2017

Characteristics of optical multi-peak solitons induced by higher-order effects in an erbium-doped fiber system

We study multi-peak solitons \textit{on a plane-wave background} in an erbium-doped fiber system with some higher-order effects, which is governed by a coupled Hirota and Maxwel-Bloch (H-MB) model. The important characteristics of multi-peak solitons induced by the higher-order effects, such as the velocity changes, localization or periodicity attenuation, and state transitions, are revealed in detail. In particular, our results demonstrate explicitly that a multi-peak soliton can be converted to an anti-dark soliton when the periodicity vanishes; on the other hand, a multi-peak soliton is transformed to a periodic wave when the localization vanishes. Numerical simulations are performed to confirm the propagation stability of multi-peak solitons riding on a plane-wave background. Finally, we compare and discuss the similarity and difference of multi-peak solitons in special degenerate cases of the H-MB system with general existence conditions.

nlin.PS↗

arXiv2017

Dynamics of Rogue Wave Excitation Pattern on Stripe Phase Backgrounds in a Two-component Bose-Einstein Condensate

We study rogue wave excitation pattern in a two-component Bose-Einstein condensate with pair-transition effects. The results indicate that rogue wave excitation can exist on a stripe phase background for which there are cosine and sine wave background in the two components respectively. The rogue wave peak can be much lower than the ones of scalar matter wave rogue waves, and varies with the wave period changing. Both rogue wave pattern and rogue wave number on temporal-spatial plane are much more abundant than the ones reported before. Furthermore, we prove that the rogue wave number can be $n (n+1)/2+m (m+1)/2$ (where $m,n $ are arbitrary non-negative integers), in contrast to $n(n+1)/2$ for scalar nonlinear Schrödinger equation described systems. These results would enrich our knowledge on nonlinear excitations in multi-component Bose-Einstein condensate with transition coupling effects.

nlin.PS↗

arXiv2016

Stable Soliton Excitations in Modulational Instability Regime with the Fourth-order Effects

We study the correspondence between modulational instability and types of fundamental nonlinear excitation in a nonlinear fiber with both third-order and fourth-order effects. Some stable soliton excitations are obtained in modulational instability regime, which have not been found in nonlinear fibers with second-order effects and third-order effects. Explicit analysis suggests that the stable soliton existence is related with the modulation stability circle in the modulation instability regime, and they just exist in the modulational instability regime outside of the modulational stability circle. It should be emphasized that the stable soliton just exist with two special profiles on a continuous wave background with certain frequency. The evolution stability of the solitons is tested numerically, which indicate they are robust against perturbations even in modulation instability regime. The further analysis indicates that the solitons in modulational instability regime are caused by the fourth-order effects.

nlin.PS↗

arXiv2016

Tunneling Dynamics Between Atomic Bright Solitons

We investigate tunneling behavior between two bright solitons in a Bose-Einstein condensate with attractive contact interactions between atoms. The explicit tunneling properties including tunneling particles and oscillation period are described analytically, which indicates that the periodic tunneling form is a nonlinear Josephson type oscillation. The results suggest that the breathing behavior of solitons comes from the tunneling mechanism in an effective double-well potential, which is quite different from the modulational instability mechanism for Akhmediev breather and K-M breather. Furthermore, we obtain a phase diagram for two soliton interaction which admits tunneling property, particle-like property, interference property, and a resonant interaction case. The explicit conditions for them are clarified based on the defined critical distance $d_c$ and spatial interference period $D$.

nlin.PS↗

arXiv2016

Symmetric and asymmetric optical multi-peak solitons on a continuous wave background in the femtosecond regime

We study symmetric and asymmetric optical multi-peak solitons on a continuous wave background in the femtosecond regime of a single-mode fiber. Key characteristics of such multi-peak solitons, as the formation mechanism, propagation stability, and shape-changing collisions, are revealed in detail. Our results show that this multi-peak (symmetric or asymmetric) mode could be regarded as a single pulse formed by a nonlinear superposition of a periodic wave and a single-peak (W-shaped or antidark) soliton. In particular, a phase diagram for different types of nonlinear excitations on a continuous wave background including breather, rogue wave, W-shaped soliton, antidark soliton, periodic wave, and multi-peak soliton is established based on the explicit link between exact nonlinear wave solution and modulation instability analysis. Numerical simulations are performed to confirm the propagation stability of the multi-peak solitons with symmetric and asymmetric structures. Further, we unveil a remarkable shape-changing feature of asymmetric multi-peak solitons. It is interesting that these shape-changing interactions occur not only in the intraspecific collision (soliton mutual collision) but also in the interspecific interaction (soliton-breather interaction). Our results demonstrate that each multi-peak soliton exhibits the coexistence of shape change and conservation of the localized energy of light pulse against the continuous wave background.

nlin.PS↗

arXiv2016

Prolific interaction structures and shape-changing collisions in an erbium-doped fiber system

Prolific interactions of nonlinear waves on a plane-wave background in an erbium-doped fiber system are unveiled, based on explicit coexistence conditions extracting from the general higher-order solution of a coupled nonlinear Schrödinger and the Maxwell-Bloch equations. In contrast to previous results, it shows that rich different types of nonlinear waves can coexist and interact with each other. In particular, we reveal an interesting kind of shape-changing collision, in which the multi-peak solitons exhibit intensity redistribution characteristics. This interaction involves the mutual collision between multi-peak solitons as well as the interplay of multi-peak soliton and other types of localized nonlinear waves (breather and antidark soliton). We find that the shape-changing collision preserves the power of each multi-peak soliton, which is verified via optimal numerical integration for the energy of light pulse against the plane-wave background. Our results demonstrate that when the interactions occur, each multi-peak soliton exhibits the coexistence of the shape change and energy conservation.

nlin.PS↗

arXiv2016

Different types of nonlinear localized and periodic waves in an erbium-doped fiber system

We study nonlinear waves on a plane-wave background in an erbium-doped fiber system, which is governed by the coupled nonlinear Schrödinger and the Maxwell-Bloch equations. We find that prolific different types of nonlinear localized and periodic waves do exist in the system, including multi-peak soliton, periodic wave, antidark soliton, and W-shaped soliton (as well as the known bright soliton, breather, and rogue wave). In particular, the dynamics of these waves can be extracted from a unified exact solution, and the corresponding existence conditions are presented explicitly. Our results demonstrate the structural diversity of the nonlinear waves in this system.

nlin.PS↗

arXiv2015

Small polaron with generic open boundary conditions revisit: exact solution via the off-diagonal Bethe ansatz

The small polaron, an one-dimensional lattice model of interacting spinless fermions, with generic non-diagonal boundary terms is studied by the off-diagonal Bethe ansatz method. The presence of the Grassmann valued non-diagonal boundary fields gives rise to a typical $U(1)$-symmetry-broken fermionic model. The exact spectra of the Hamiltonian and the associated Bethe ansatz equations are derived by constructing an inhomogeneous $T-Q$ relation.

math-ph↗

arXiv2014

Critical behaviors of black holes in the Einstein-Maxwell gravity with conformal anomaly

We study $P-V$ critical behavior of 4-dimensional AdS black hole in the Einstein-Maxwell gravity with conformal anomaly by treating the cosmological constant as a variable related to the thermodynamic pressure. It shows that there is no phase transition if taking $k=0$ or -1. When the charge $q_1$ of conformal field and the coefficient $α$ satisfy a certain relation, the Van der Waal like phase transition for the spherical black hole can occur in case of the temperature is lower than the small critical temperature or higher than the large one. We also evaluate the critical exponents of the phase transitions and find that the thermodynamic exponents associated with this 4-dimensional AdS black hole coincide with those of the van der Waals fluid.

hep-th↗

arXiv2014

$P-V$ criticality of AdS black hole in the Einstein-Maxwell-power-Yang-Mills gravity

We study the $P-V$ critical behaivor of N-dimensional AdS black holes in Einstein-Maxwell-power-Yang-Mills gravity. Our results show the existence of the Van der Waals like small-large black hole phase transitions when taking some special values of charges of the Maxwell and Yang-Mills (YM) fields. Further to calculate the critical exponents of the black holes at the critical point, we find that they are the same as those in the Van der Waals liquid-gas system.

hep-th↗

arXiv2014

State Transition Induced by Higher-order Effects and Background Frequency

State transition between the Peregrine rogue wave and w-shaped traveling wave induced by higher-order effects and background frequency is studied. We find that this intriguing transition, described by an exact explicit rational solution, is consistent with the modulation instability (MI) analysis that involves MI region and stability region in low perturbation frequency region. In particular, the link between the MI growth rate and transition characteristic analytically demonstrates that, the size characteristic of transition is positively associated with the reciprocal of zero-frequency growth rate. Further, we investigate the case for nonlinear interplay of multi-localized waves. It is interesting that the interaction of second-order waves in stability region features a line structure, rather than an elastic interaction between two w-shaped traveling waves.

nlin.PS↗