论文标题
选择后和量子能量学
Post-selection and quantum energetics
论文作者
论文摘要
我们研究了测量设备的异常能量变化时，当量子位在不通过能量上市的碱基中测量时。我们对两个可能的测量实现进行了建模：一个是具有完全独立时间的哈密顿量的量子时钟模型，而另一个是Jaynes-Cummings模型，它是时间依赖性的，但可以保留总的激发数。我们查看两个模型中测量设备的平均能量变化，以量子的结论为条件，发现这种变化可以大得多，远大于量子的水平间距，例如异常的弱值。在时钟模型中，设备能量转移的表达式明确包含量子哈密顿量的弱值。但是，在我们的情况下，未进行明确的弱测量。我们的两个模型给出了不同的结果，我们将其解释为Jaynes-Cummings模型的非分类光谱的结果。我们将Jaynes-Cummings模型中的计算与[J.的实验数据进行了比较。 Stevens等人，Arxiv：2109.09648（2021）]并在我们的派生条件有效时找到良好的一致性。
We investigate the anomalous energy change of the measurement apparatus when a qubit is measured in bases that do not commute with energy. We model two possible measurement implementations: one is a quantum clock model with a completely time-independent Hamiltonian, while the other is a Jaynes-Cummings model which is time-dependent but conserves the total excitation number. We look at the mean energy change of the measurement apparatus in both models, conditioned on the qubit post-selection, and find that this change can be much greater than the level spacing of the qubit, like an anomalous weak value. In the clock model, the expression for the apparatus energy shift explicitly contains the weak value of the qubit Hamiltonian. However, in our case, no explicit weak measurements are carried out. Our two models give different results, which we explain to be a consequence of the non-degenerate spectrum of the Jaynes-Cummings model. We compare our calculations in the Jaynes-Cummings model with the experimental data of [J. Stevens, et al, arXiv:2109.09648 (2021)] and find good agreement when the conditions of our derivation are valid.
