Spin-Based Quantum Processor and Spectrometer

这个项目是为了实现对基于自旋的量子设备的完全量子控制。自旋是最多功能的量子系统之一，已经在传感、纠缠产生以及作为量子计算机的试验台方面得到了应用。最初的隐形传态、肖尔算法和纠错都是用自旋完成的。今天，有大量基于量子自旋的传感器正在开发，从医疗设备到导航工具无所不包。然而，尽管有了这些发展，量子的大部分力量还没有在自旋处理器中获得，因为自旋与其控制系统的相互作用非常弱。事实上，它是如此微弱，以至于可以很好地近似地认为这些控制是经典的。*我们开发了新的控制元件和方案，其中自旋/控制器相互作用很强，并且相互作用是完全量子的。有了这些新工具，量子设备就能变得更高效、更精确、更灵敏。这些控制是超导电路，当与自旋相互作用时，提供更快的门，并可以根据需要冷却和挤压自旋态。冷却可以并行去除熵，这是所有量子设备的关键一步，也是量子纠错的关键一步。压缩可以产生纠缠，更精确地传感，是连续变量量子计算的基础。*这一进步为自旋物理带来了高度的协作性。除了为自旋启用新的控制元件外，它还开辟了大N域中的腔量子电动力学(QED)的新领域，即具有大量自旋的自旋/腔物理。我们预计，该系统将成为凝聚态物质和材料科学模拟的工具。我们可以通过实验探索的新物理包括理论难以解决的多体物理领域。拥有第一个探索这种物理的试验台的例子应该会带来新的见解。*最后，自旋是最相干的量子系统之一，应该会成为优秀的光子存储元件。具有高度的协作性是将其用于微波存储和潜在的光子转换的途径。这是一条通往量子中继器的可能路径。

This project is to implement fully quantum control over spin-based quantum devices. Spins are some of the most versatile quantum systems and have found applications in sensing, entanglement generation, and as testbeds for quantum computers. The first examples of teleportation, Shor's algorithm and error correction were all done with spins. Today there are a wealth of quantum spin-based sensors being developed for everything from medical devices to navigational tools. Yet despite these developments, much of the power of quantum has not been available with spin processors since spins interact only very weakly with their control system. So weakly in fact, that it is a good approximation to think of the controls as classical. ******We have developed new control elements and schemes where the spin/controller interaction is strong and the interaction is fully quantum. Having these new tools enables quantum devices that are more efficient, precise and sensitive. The controls are superconducting circuits and, when interacting with spins, provide faster gates and can cool and squeeze spin states on demand. Cooling allows parallel removal of entropy, a key step for all quantum devices and an essential one for quantum error correction. Squeezing allows entanglement generation, more precise sensing, and is the foundation for quantum computing with continuous variables. ******This advance brings high cooperativity to spin physics. Beyond enabling new control elements for spins it also opens the new area of cavity quantum electrodynamics (QED) in the large-N domain, or spin/cavity physics with lots of spins. We anticipate that this system will become a tool for condensed matter and materials science simulations. The new physics we can experimentally explore include areas of multi-body physics where the theory is intractable. Having a first example of a testbed to explore such physics should bring new insight.******Finally, spins are some of the most coherent quantum systems and should make excellent photon storage elements. Having a high cooperativity is a path to using these for microwave storage and potentially photon transduction. It is a possible path to a quantum repeater.