论文标题
在NMR量子模拟器中观察相互作用引起的封锁和局部自旋冻结
Observation of interaction induced blockade and local spin freezing in a NMR quantum simulator
论文作者
论文摘要
我们在两个和三个Qubit核磁共振(NMR)结构中实验模拟了相互作用引起的封锁和局部自旋冷冻。这些现象与Rydberg的封锁和Rydberg相同。在Rydberg封锁中,由于强大的范德华的相互作用引起的水平移位,两个或多个原子的同时激发被阻断。在如此强大的互动状态下,人们还可以观察到Rydberg有偏见的冻结,其中,动力学仅限于子空间,借助多个驱动器,具有不平等的振幅。在这里,我们驱动具有特定过渡选择的无线电波的NMR量子位,同时通过量子状态层析成像表征量子状态。这不仅使我们能够跟踪人口动态,而且还可以通过量子不一调,在阻断和冻结现象下发展,有助于探测量子相关性。虽然我们的工作构成了NMR平台中这些现象的第一个实验模拟,但它也是Rydberg偏向冻结的第一个实验证明。此外,这些研究开辟了有趣的量子控制观点,以利用上述现象进行纠缠产生以及子空间操作。
We experimentally emulate interaction induced blockade and local spin freezing in two and three qubit Nuclear Magnetic Resonance (NMR) architecture. These phenomena are identical to the Rydberg blockade and Rydberg biased freezing. In Rydberg blockade, the simultaneous excitation of two or more atoms is blocked due to the level shift induced by the strong Van der Waal's interaction. In such a strong interaction regime, one can also observe Rydberg biased freezing, wherein the dynamics is confined to a subspace, with the help of multiple drives with unequal amplitudes. Here we drive NMR qubits with specific transition-selective radio waves, while intermittently characterizing the quantum states via quantum state tomography. This not only allows us to track the population dynamics, but also helps to probe quantum correlations, by means of quantum discord, evolving under blockade and freezing phenomena. While, our work constitutes the first experimental simulations of these phenomena in the NMR platform, it is also the first experimental demonstration of Rydberg biased freezing. Moreover, these studies open up interesting quantum control perspectives in exploiting the above phenomena for entanglement generation as well as subspace manipulations.