Controlling transition probability from matter-wave soliton to chaos

Chaos-assisted formation of immiscible matter-wave solitons and self-stabilization in the binary discrete nonlinear Schrödinger equation

Binary discrete nonlinear Schrödinger equation is used to describe dynamics of two-species Bose-Einstein condensate loaded into an optical lattice. Linear inter-species coupling leads to Rabi transitions between the species. In the regime of strong nonlinearity, a wavepacket corresponding to condensate separates into localized and ballistic fractions. Localized fraction is predominantly formed by immiscible solitons consisted of only one species. Initial states without spatial separation of occupied sites expose formation of immiscible solitons after a strongly chaotic transient. We calculate …

Hidden possibilities in controlling optical soliton in fiber guided doped resonant medium

Fiber guided optical signal propagating in a Erbium doped nonlinear resonant medium is known to produce cleaner solitonic pulse, described by the self induced transparency (SIT) coupled to nonlinear Schroedinger equation. We discover two new possibilities hidden in its integrable structure, for amplification and control of the optical pulse. Using the variable soliton width permitted by the integrability of this model, the broadening pulse can be regulated by adjusting the initial population inversion of the opant atoms. The effect can be enhanced by another innovative application of its const…

Coarse-Grained Picture for Controlling Quantum Chaos

We propose a coarse-grained picture to analyze control problems for quantum chaos systems. Using optimal control theory, we first show that almost perfect control is achieved for random matrix systems and a quantum kicked rotor. Second, under the assumption that the controlled dynamics is well described by a Rabi-type oscillaion between unperturbed states, we derive an analytic expression for the optimal field. Finally we numerically confirm that the analytic field can steer an initial state to a target state in random matrix systems.

An exact solution of the slow-light problem

We investigate propagation of a slow-light soliton in atomic vapors and Bose-Einstein condensates described by the nonlinear Lambda-model. We show that the group velocity of the soliton monotonically decreases with the intensity of the controlling laser field, which decays exponentially after the laser is switched off. The shock wave of the vanishing controlling field overtakes the slow soliton and stops it, while the optical information is recorded in the medium in the form of spatially localized polarization. We find an explicit exact solution describing the whole process within the slowly v…

Exact coherent matter-wave soliton induced and controlled by laser field

We find a set of exact solutions of coherent bright solitons in the quasi-one-dimensional (1D) Bose-Einstein condensate (BEC) trapped in a harmonic potential, by using a Gaussian laser well (barrier) with oscillating position to balance the repulsive (attractive) interatomic interaction. The bright solitons do not deform in propagation and are controlled accurately by the laser driving which resonates with the trapping potential. The solitonic motion is more stable for the repulsive BEC than that of the attractive BEC. The results reveal a different kind of soliton trains compared to that repo…

Regular and chaotic Bose-Einstein condensate in an accelerated Wannier-Stark lattice

We investigate a Bose-Einstein condensate held in a quasi-one-dimensional Wannier-Stark lattice which is a combination of linear potential with an accelerated optical lattice. It is demonstrated that the system can be reduced to a periodically driven Gross-Pitaevskii one, in which we find the first exact analytical solution and the regular and chaotic numerical solutions with accelerated atomic flow densities. The results suggest an experimental scheme for generating and controlling the accelerating regular and chaotic matter-waves.

控制量子混沌：含时 kicked rotor

Controlling quantum chaos: time-dependent kicked rotor

本文扩展了量子混沌控制方法，提出一种无需抵消量子态扩散的含时局部稳定控制哈密顿量，应用于量子 kicked rotor，实现更简单且实验可行的近似控制，误差随普朗克常数趋于零而消失。

在耗散光学腔中控制多体量子混沌

Controlling many-body quantum chaos in a dissipative optical cavity

研究典型腔QED设置的驱动耗散动力学，含可控无序和长程相互作用。发现腔损耗和自发辐射这两个耗散源结构不同，导出腔QED平台中多体量子混沌观测与控制的定量约束。

在含噪声中等规模量子硬件上通过Parrondo策略控制量子混沌

Controlling quantum chaos via Parrondo strategies on noisy intermediate-scale quantum hardware

针对NISQ系统的量子混沌控制问题，本研究基于Parrondo策略，利用经QFT优化的DTQW在三台NISQ设备上实现混沌到有序的转变，验证了该方案的可行性与应用价值。

控制多体量子混沌：Bose-Hubbard系统

Controlling Many-Body Quantum Chaos: Bose-Hubbard systems

本文提出通过引入控制哈密顿量，在混沌区域的Bose-Hubbard系统中利用不稳定平均场解实现相干量子目标导向，从而快速制备特殊量子态并稳定量子多体疤痕，为光学晶格实验提供了化学势时变控制方案。

Self-organised Limit-Cycles, Chaos and Phase-Slippage with a Superfluid inside an Optical Resonator

We study dynamical phases of a driven Bose-Einstein condensate coupled to the light field of a high-Q optical cavity. For high field seeking atoms at red detuning the system is known to show a transition from a spatially homogeneous steady-state to a self-organized regular lattice exhibiting super-radiant scattering into the cavity. For blue atom pump detuning the particles are repelled from the maxima of the light-induced optical potential suppressing scattering. We show that this generates a new dynamical instability of the self-ordered phase, leading to the appearance of self-ordered stable…