Learn More
We demonstrate a decoherence-free quantum memory of one qubit. By encoding the qubit into the decoherence-free subspace (DFS) of a pair of trapped 9Be+ ions, we protect the qubit from environment-induced dephasing that limits the storage time of a qubit composed of a single ion. We measured the storage time under ambient conditions and under interaction(More)
We experimentally investigate three methods, utilizing different atomic observables and entangled states, to increase the sensitivity of rotation angle measurements beyond the "standard quantum limit" for nonentangled states. All methods use a form of quantum mechanical "squeezing." In a system of two entangled trapped (9)Be(+) ions we observe a reduction(More)
Local realism is the idea that objects have definite properties whether or not they are measured, and that measurements of these properties are not affected by events taking place sufficiently far away. Einstein, Podolsky and Rosen used these reasonable assumptions to conclude that quantum mechanics is incomplete. Starting in 1965, Bell and others(More)
We show how an experimentally realized set of operations on a single trapped ion is sufficient to simulate a wide class of Hamiltonians of a spin-1/2 particle in an external potential. This system is also able to simulate other physical dynamics. As a demonstration, we simulate the action of two nth order nonlinear optical beam splitters comprising an(More)
Using a single, harmonically trapped 9Be(+) ion, we experimentally demonstrate a technique for generation of arbitrary states of a two-level particle confined by a harmonic potential. Rather than engineering a single Hamiltonian that evolves the system to a desired final state, we implement a technique that applies a sequence of simple operations to(More)
We review recent experiments on entanglement, Bell's inequality , and decoherence-free subspaces in a quantum register of trapped 9 Be + ions. We have demonstrated entangle-ment of up to four ions [1] using the technique of Mølmer and Sørensen [2]. This method produces the state (|↑↑+|↓↓)/ √ 2 for two ions and the state (| ↓↓↓↓ + | ↑↑↑↑)/ √ 2 for four ions.(More)
We report experiments on coherent quantum-state synthesis and the control of trapped atomic ions. This work has the overall goal of performing large-scale quantum information processing; however, such techniques can also be applied to fundamental tests and demonstrations of quantum mechanical principles, as well as to the improvement of quantum-limited(More)
VJe describe the underlying concept and experimental demonstration of the basic building bloclts of a scalable quantum information processor archikcture using trapped ion-clubits. The trap structure is divided into many subregions. In eacl~ several ion-qubits can be trapped in complete isolation from all the other ion-qubits in the system. In a particular(More)
  • 1