Quantum Gates and Small Cluster States with Trapped Neutral Atoms

我们计划研究中性原子的小弦在量子信息处理中的应用。原子被一个接一个地存储在驻波偶极阱中，原子之间的相互作用，对于实现量子门是必要的，将通过受控的冷碰撞来实现。为此，我们将采用自旋相关输运技术。这种技术将允许我们在确定性和完全受控的单原子Stern-Gerlach实验中手动分裂被困原子的波函数，其中偶极阱提供有效磁场。通过重新组合原子波函数，我们将实现单原子干涉仪，并直接测量分裂过程的相干性。在单个原子上进行的一系列分裂操作将产生一个类似于加仑板的量子模拟，其中原子进行量子行走。这种量子行走最近被提出作为量子计算的替代方法。我们的最终目标是在2-10个被困中性原子的寄存器内使用受控冷碰撞实现基本量子门。这样的量子门的并行应用应该打开了制备由多达10个可单独寻址的量子位组成的小簇态的途径。

We plan to investigate small strings of neutral atoms for applications in quantum information processing. The atoms are stored, one by one, in a standing wave dipole trap and the interaction between the atoms, necessary for the implementation of quantum gates, will be realized through controlled cold collisions. For this, we will employ the technique of spin dependent transport. This technique will allows us to manually split the wave functions of the trapped atoms in a deterministic and fully controlled single atom Stern-Gerlach experiment, where the dipole trap provides the effective magnetic field. By recombining the atomic wave function, we will then realize a single atom interferometer and directly measure the coherence properties of the splitting process. A sequence of splitting operations, carried out on a single atom, will result in a quantum analogue of the Gallon board, where the atom carries out a quantum walk. Such quantum walks have recently been proposed as an alternative approach to quantum computing. Our ultimate goal is the implementation of fundamental quantum gates using controlled cold collisions within a register of 2-10 trapped neutral atoms. A parallel application of such quantum gates should then open the route towards the preparation of small cluster states consisting of up to 10 individually addressable qubits.