Quantum steering in a system consisting of a qubit coupled to a single-mode field are explored when classical-like measurements implemented by heterodyne detection schemes that collapse the state of the field on to a coherent state are considered with the aim of constructing the generalized quantum steering ellipsoid for the qubit. The steering ellipsoid of the qubit enables visualization of the set of states on to which it can be steered using such measurements. In some cases, the steering set does not form an ellipsoid since only heterodyne detection is considered. This is particularly the case when the initial qubit-field state is mixed. The structure of the steering set is explored in detail for this case with representative examples. Evolution of the steering ellipsoid corresponding to joint evolution of the qubit and field under the Jaynes–Cummins Hamiltonian is also studied.

中文翻译：

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量子位场系统的广义量子转向椭球

当考虑通过外差检测方案实现的将电场状态坍缩为相干状态的经典测量方法进行研究时，探索了由量子位耦合到单模场组成的系统中的量子转向量子位的转向椭球。量子位的转向椭球体可以显示使用此类测量值可以转向的状态集。在某些情况下，由于仅考虑外差检测，因此转向装置不形成椭球。当初始量子位域状态混合时，尤其如此。对于这种情况，将通过具有代表性的示例详细探讨转向装置的结构。