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We investigate the adiabatic evolution of light in nonlinear waveguide couplers via resonance-locked inverse engineering based on stimulated Raman adiabatic passage (STIRAP). The longitudinal varying detunings of the propagation coefficients are designed to eliminate dynamically the nonlinear effect, which induce the non-adiabatic oscillations. We show that different light evolutions such as complete light transfer, light split and light return can be realized adiabatically with appropriate choices of the detunings even in the nonlinear regime. The features open new opportunities for the realization of all-optical nonlinear devices with high fidelity in integrated optics., Comment: 8 pages,6 figures

Quantum batteries are energy storage devices that satisfy quantum mechanical principles. How to obtain analytical solutions for quantum battery systems and achieve a full charging is a crucial element of the quantum battery. Here, we investigate the Rosen-Zener quantum battery with $N$ two-level systems, which includes atomic interactions and external driving field. The analytical solutions of the stored energy, changing power, energy quantum fluctuations, and von Neumann entropy are derived by employing the gauge transformation. We demonstrate that full charging process can be achieved when the external driving field strength and scanning period conforms to a quantitative relationship. The local maximum value of the final stored energy corresponds to the local minimum values of the final energy fluctuations and von Neumann entropy. Moreover, we find that the atomic interaction induces the quantum phase transition and the maximum stored energy of the quantum battery reaches the maximum value near the quantum phase transition point. Our result provides an insightful theoretical scheme to realize the efficient quantum battery., Comment: 9 pages,7 figures

We investigate the performance of the Lipkin-Meshkov-Glick quantum battery based on shortcuts to adiabaticity (STA). We mainly consider the situation where the coupling strength of any two sites in the quantum battery is a sinusoidal function with respect to time. The charging efficiency of the quantum battery can be greatly enhanced via STA. We also analyze the influences of parameters, including particle number, anisotropic parameter, the amplitude and frequency of the driving fields. It is found that an efficient charging process and thus high charging advantages can be achieved by adjusting these parameters properly. Moreover, we calculate the energy fluctuation, von Neumann entropy and energy cost during charging. The STA can make the stored energy and the von Neumann entropy change periodically during the charging process and reduce the energy fluctuation, and the minimal energy fluctuation always occurs in the proximity of minima of the von Neumann entropy., 8 pages,5 figures

The quantum speed limit (QSL) represents the cornerstone of essential physical limit on the speed of evolution process in quantum mechanics. To derive the QSL for arbitrary quantum systems, here we present a geometric method, which is estiblished on the quantum brachistochrone characterized by the Riemannian metric. As an application to the complex quantum system, we consider the nonlinear Landau-Zener type two-level system, representing coherent atoms for BECs with mean-field interaction. The analytical expression of the quantum brachistochrone and population are obtained for the nonlinear system. We further derive the corresponding optimal procotol and demonstrate that the QSL is tight. We also generalize our formulation to open quantum systems., Comment: 5+3 pages,1+1 figures

The Su-Schrieffer-Heeger (SSH) model has recently received considerable attention in condensed matter because it describes a typical one-dimensional system with topological edge states. Here, we investigate SSH-based charging protocols of quantum batteries (QB) with N quantum cells. This SSH QB hopping interaction induced ground state splitting makes the different effects of the dimerize parameter to the QB in the different quantum phase region. In the non-splitting region, the dimerize parameter has little influence on the QB. Whereas the fully-splitting region, the dimerize parameter has a significantly quantum advantage to the energy and ergotropy in the ground state fully splitting region, which leads the dimerize spin couples will have larger occupations than other spins. Although we have enhanced energy and ergotropy by the dimerize parameter, QB's capacity will decrease.