Controlling long-distance quantum correlations is central to quantum computation and simulation. In quantum dot arrays, experiments so far rely on nearest-neighbour couplings only, and inducing long-distance correlations requires sequential local operations. Here, we show that two distant sites can be tunnel-coupled directly. The coupling is mediated by virtual occupation of an intermediate site, with a strength that is controlled via the energy detuning of this site. It permits a single charge to oscillate coherently between the outer sites of a triple dot array without passing through the middle, as demonstrated through the observation of Landau–Zener–Stückelberg interference. The long-distance coupling significantly improves the prospects of fault-tolerant quantum computation using quantum dot arrays, and opens up new avenues for performing quantum simulations in nanoscale devices.
At a glance
- Quantum computation with quantum dots. Phys. Rev. A 47, 120–126 (1998). &
- Fault-tolerant architecture for quantum computation using electrically controlled semiconductor spins. Nature Phys. 1, 177–183 (2005). et al.
- Spins in few-electron quantum dots. Rev. Mod. Phys. 79, 1217–1265 (2007). , , , &
- Coherent manipulation of electronic states in a double quantum dot. Phys. Rev. Lett. 91, 226804 (2003). , , , &
- Microwave spectroscopy of a quantum-dot molecule. Nature 395, 873–876 (1998). et al.
- Manipulation of a single charge in a double quantum dot. Phys. Rev. Lett. 93, 186802 (2004). , , , &
- Coherent manipulation of coupled electron spins in semiconductor quantum dots. Science 309, 2180–2184 (2005). et al.
- Single-shot correlations and two-qubit gate of solid-state spins. Science 333, 1269–1272 (2011). et al.
- High-threshold universal quantum computation on the surface code. Phys. Rev. A 80, 052312 (2009). , &
- Accuracy threshold for concatenated error detection in one dimension. Phys. Rev. A 80, 022313 (2009). &
- Quantum simulation of frustrated Ising spins with trapped ions. Nature 465, 590–593 (2010). et al.
- 293–306 (Kluwer Academic, 2001). , & in Macroscopic Quantum Coherence and Quantum Computing
- 2006). The Theory of Magnetism made Simple (World Scientific,
- Realization of the Cirac–Zoller controlled-NOT quantum gate. Nature 422, 408–411 (2003). et al.
- Coupling superconducting qubits via a cavity bus. Nature 449, 443–447 (2007). et al.
- Coherent quantum state storage and transfer between two phase qubits via a resonant cavity. Nature 449, 438–442 (2007). , &
- Quantum information processing using quantum dot spins and cavity QED. Phys. Rev. Lett. 83, 4204–4207 (1999). et al.
- Cavity quantum electrodynamics with semiconductor double-dot molecules on a chip. Preprint at http://arxiv.org/abs/cond-mat/0605144v1 (2006). &
- Ultra-long-distance interaction between spin qubits. Phys. Rev. B 74, 041307(R) (2006). et al. &
- Spin dynamics in InAs nanowire quantum dots coupled to a transmission line. Phys. Rev. B 77, 045434 (2008). , &
- Dipole coupling of a double quantum dot to a microwave resonator. Phys. Rev. Lett. 108, 046807 (2012). et al.
- Circuit quantum electrodynamics with a spin qubit. Nature 490, 380–383 (2012). et al.
- Electrons surfing on a sound wave as a platform for quantum optics with flying electrons. Nature 477, 435–438 (2011). et al.
- On-demand single-electron transfer between distant quantum dots. Nature 477, 439–442 (2011). et al.
- Spin qubits in graphene quantum dots. Nature Phys. 3, 192–196 (2007). , , &
- 2010). Semiconductor Nanostructures: Quantum states and Electronic Transport (Oxford Univ. Press,
- Fast single-charge sensing with a rf quantum point contact. Appl. Phys. Lett. 91, 162101 (2007). , , &
- Bipolar spin blockade and coherent state superpositions in a triple quantum dot. Nature Nanotech. 8, 261–265 (2013). et al.
- Electron counting in quantum dots. Surf. Sci. Rep. 64, 191–232 (2009). et al.
- Electron transport through double quantum dots. Rev. Mod. Phys. 75, 1–22 (2003). et al.
- Landau–Zener–Stückelberg interferometry. Phys. Rep. 492, 1–30 (2010). , &
- Molecular Collision Theory (Dover Publications, 1974).
- 1984). & Theory of Slow Atomic Collisions (Springer,
- Mach–Zehnder interferometry in a strongly driven superconducting qubit. Science 310, 1653–1657 (2005). et al.
- A coherent beam splitter for electronic spin states. Science 327, 669–672 (2010). , &
- Origin of switching noise in GaAs/AlxGa1–xAs lateral gated devices. Phys. Rev. B 72, 115331 (2005). et al.
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