The observation of genuine quantum effects in systems governed by non-Hermitian Hamiltonians has been an outstanding challenge in the field. Here we simulate the evolution under such Hamiltonians in the quantum regime on a superconducting quantum processor by using a dilation procedure involving an ancillary qubit. We observe the parity–time (\({\mathcal{PT}}\))-symmetry breaking phase transition at the exceptional points, obtain the critical exponent, and show that this transition is associated with a loss of state distinguishability. In a two-qubit setting, we show that the entanglement can be modified by local operations.

中文翻译：

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用超导量子处理器对奇偶时间对称性破坏的量子模拟

在非埃尔米特哈密顿量控制的系统中，观察真正的量子效应一直是该领域的一项严峻挑战。在这里，我们通过使用涉及辅助量子位的扩张程序，在超导量子处理器上模拟了这种哈密顿量在量子状态下的演化。我们在奇数点观察奇偶-时间（\（{\ mathcal {PT}} \））对称性破坏相变，获得临界指数，并表明该转变与状态可分辨性的丧失有关。在两个量子位的设置中，我们表明纠缠可以通过本地操作进行修改。