Heat Modulation on Target Thermal Bath via Coherent Auxiliary Bath.

We study a scheme of thermal management where a three-qubit system assisted with a coherent auxiliary bath (CAB) is employed to implement heat management on a target thermal bath (TTB). We consider the CAB/TTB being ensemble of coherent/thermal two-level atoms (TLAs), and within the framework of collision model investigate the characteristics of steady heat current (also called target heat current (THC)) between the system and the TTB. It demonstrates that with the help of the quantum coherence of ancillae the magnitude and direction of heat current can be controlled only by adjusting the coupling strength of system-CAB. Meanwhile, we also show that the influences of quantum coherence of ancillae on the heat current strongly depend on the coupling strength of system-CAB, and the THC becomes positively/negatively correlated with the coherence magnitude of ancillae when the coupling strength below/over some critical value. Besides, the system with the CAB could serve as a multifunctional device integrating the thermal functions of heat amplifier, suppressor, switcher and refrigerator, while with thermal auxiliary bath it can only work as a thermal suppressor. Our work provides a new perspective for the design of multifunctional thermal device utilizing the resource of quantum coherence from the CAB.

Reservoir-engineered entanglement in optomechanical systems.

We show how strong steady-state entanglement can be achieved in a three-mode optomechanical system (or other parametrically coupled bosonic system) by effectively laser cooling a delocalized Bogoliubov mode. This approach allows one to surpass the bound on the maximum stationary intracavity entanglement possible with a coherent two-mode squeezing interaction. In particular, we find that optimizing the relative ratio of optomechanical couplings, rather than simply increasing their magnitudes, is essential for achieving strong entanglement. Unlike typical dissipative entanglement schemes, our results cannot be described by treating the effects of the entangling reservoir via a Linblad master equation.

Using interference for high fidelity quantum state transfer in optomechanics.

We revisit the problem of using a mechanical resonator to perform the transfer of a quantum state between two electromagnetic cavities (e.g., optical and microwave). We show that this system possesses an effective mechanically dark mode which is immune to mechanical dissipation; utilizing this feature allows highly efficient transfer of intracavity states, as well as of itinerant photon states. We provide simple analytic expressions for the fidelity for transferring both gaussian and non-gaussian states.

Molecular reaction mechanism for elimination of zearalenone during simulated alkali neutralization process of corn oil.

Zearalenone (ZEN) is one of the most widely distributed harmful mycotoxins produced by Fusarium species, especially deposited in corn oil. In this study, we systematically tracked the changes of ZEN in the refining of corn oil, and especially during neutralization process. An alkali neutralization process could remove certain amounts of ZEN that was much more than that of others refining steps. In a mimicking condition, ZEN contents decreased continuously and significantly with increasing neutralization temperature. However, when returned to neutral, recoverable ZEN decreased with increasing temperature, which confirmed more degradation of ZEN at high temperature. HPLC-Q/TOF MS and NMR evidence showed that non-reversible hydrolyzate followed decarboxylation was observed in a high-temperature alkali neutralization condition. The results may serve as the scientific basis for the elimination of zearalenone in refined vegetable oils, and provide clues to understanding the oil-safety aspects of elimination of zearalenone.

Diabolical points in multi-scatterer optomechanical systems.

Diabolical points, which originate from parameter-dependent accidental degeneracies of a system's energy levels, have played a fundamental role in the discovery of the Berry phase as well as in photonics (conical refraction), in chemical dynamics, and more recently in novel materials such as graphene, whose electronic band structure possess Dirac points. Here we discuss diabolical points in an optomechanical system formed by multiple scatterers in an optical cavity with periodic boundary conditions. Such configuration is close to experimental setups using micro-toroidal rings with indentations or near-field scatterers. We find that the optomechanical coupling is no longer an analytic function near the diabolical point and demonstrate the topological phase arising through the mechanical motion. Similar to a Fabry-Perot resonator, the optomechanical coupling can grow with the number of scatterers. We also introduce a minimal quantum model of a diabolical point, which establishes a connection to the motion of an arbitrary-spin particle in a 2D parabolic quantum dot with spin-orbit coupling.