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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. [ABSTRACT FROM AUTHOR]

Quantum batteries are energy storage devices that satisfy quantum mechanical principles. How to improve the battery's performance such as stored energy and power is a crucial element in the quantum battery. Here, we investigate the charging and discharging dynamics of a three-level counterdiabatic stimulated Raman adiabatic passage quantum battery via shortcuts to adiabaticity, which can compensate for undesired transitions to realize a fast adiabatic evolution through the application of an additional control field to an initial Hamiltonian. The scheme can significantly speed up the charging and discharging processes of a three-level quantum battery and obtain more stored energy and higher power compared with the original stimulated Raman adiabatic passage. We explore the effect of both the amplitude and the delay time of driving fields on the performances of the quantum battery. Possible experimental implementation in superconducting circuit and nitrogen-vacancy center is also discussed. [ABSTRACT FROM AUTHOR]

The spin-orbit-coupled (SOC) ultracold atomic gases provide unique opportunities for exploring exotic quantum phases and introduce new capabilities into the quantum simulation. In this paper, we study the coherent control of spin states in SOC Bose–Einstein condensate (BEC) by exploiting and implementing the general concept of Landau–Zener–Stüeckelberg–Majorana (LZSM) interference. For a SOC BEC, the Landau–Zener (LZ) transition between the dressed eigenlevels occurs as the BEC is accelerated through the SOC-avoided crossing, which corresponds to a breakdown of the spin momentum locking. In our scheme, two LZ pulses are separated by an intermediate holding period of variable duration. The nice LZSM interference patterns can be generated and controlled by controlling several parameters, corresponding to coherent control of the spin state of the SOC BEC. In particular, the destructive and constructive patterns of LZSM interference are observed and well explained through analytical analysis. Our results suggest a potential application of the LZSM interferometry in calibrating the spin states of a SOC BEC. [ABSTRACT FROM AUTHOR]

We investigate the Demkov–Kunike transition in a nonlinear two-level system. We find that nonlinearity can dramatically affect the transition dynamics. We show the asymmetry of transition probability in different initial modes. For the weak interaction, the transition probability could be quickly stabilized at 100% in the initial state ψ1 and could be optionally obtained from zero to 100% over a very wide range of external parameters in the initial state ψ2. For the strong interaction, the quantum transition of the two states could be completely blocked. In the adiabatic case, for different initial modes we analyze the asymmetry of transition probability by the eigenenergy level structure of the system. We also show the influence of static detuning on transition probability. Possible applications of our theory to actual physical systems are discussed. [ABSTRACT FROM AUTHOR]

We study coherent control of a spin-orbit-coupled single atom in a double-well potential. The manipulation is achieved by applying an additional periodic driven magnetic field gradient to generate the spin-dependent force. Therefore, the strength of the spin-orbit coupling (SOC) can be continuously tuned by adjusting the driving amplitude. The atom may occupy two possible spin states which are coupled by varying fields. We show that the SOC allows controlling the interwell tunneling of the atom with or without spin-flipping and may lead to complete suppression of the tunneling at specific values of the coupling strength. By selecting the driving parameters, we propose a switchlike scheme for controlling the interwell tunneling and spin-flipping of the atom in a double-well potential. Graphical abstract: [ABSTRACT FROM AUTHOR]