Entropic uncertainty relation and entanglement of molecular dipoles in an electric field

Entropic uncertainty relation (EUR) can be improved by entangling the measured particle with a quantum memory. In this study, we consider a qutrit–qubit system consisting of two coupled molecular dipoles in an electric field, and investigate the temporal evolutions of the quantum-memory-assisted EUR and the negativity (characterizing entanglement) under intrinsic decoherence and parity-time (PT) symmetric operation. It is found that the decrease of entanglement can result in the increase of entropic uncertainty for the incompatible observables. However, the entropic uncertainty in the presence of intrinsic decoherence can be restrained by adjusting both the electric field strength and the dipole–dipole interaction, regardless of whether the initial state of the molecular system is entangled or not. Furthermore, the PT-symmetric operation is performed on one of the coupled dipoles in a state of thermal equilibrium. The results show that the intermolecular entanglement at different external temperatures can be effectively enhanced within certain time intervals, while the entropic uncertainties can be reduced simultaneously. Our findings could contribute to the development of robust quantum information processing based on polar molecules.