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Search Publications by: Dietrich Leibfried (Fed)

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Displaying 51 - 75 of 261

Versatile laser-free trapped-ion entangling gates

March 28, 2019
Author(s)
R. T. Sutherland, Raghavendra Srinivas, Shaun C. Burd, Dietrich Leibfried, Andrew C. Wilson, David J. Wineland, David T. Allcock, Daniel Slichter, S. B. Libby
We present a general theory for laser-free entangling gates with trapped-ion hyperfine qubits, using either static or oscillating magnetic-field gradients combined with a pair of uniform microwave fields symmetrically detuned about the qubit frequency. By

Quantum optimal control of the dissipative production of a maximally entangled state

December 14, 2018
Author(s)
Karl P. Horn, Florentin Reiter, Yiheng Lin, Dietrich Leibfried, Christiane P. Koch
Entanglement generation can be robust against noise in approaches that deliberately incorporate dissipation into the system dynamics. The presence of additional dissipation channels may, however, limit fidelity and speed of the process. Here we show how

Preparation and coherent manipulation of pure quantum states of a single molecular ion

May 11, 2017
Author(s)
Chin-Wen Chou, Christoph Kurz, David B. Hume, Philipp N. Plessow, David R. Leibrandt, Dietrich G. Leibfried
Laser cooling and trapping of atoms and atomic ions has led to breakthroughs in understanding of exotic phases of matter [1-3], development of exquisite sensors [4] and state-of-the-art atomic clocks [5]. For molecules, with their more complicated internal

UV-sensitive superconducting nanowire single photon detectors for integration in an ion trap

April 17, 2017
Author(s)
Daniel H. Slichter, Varun B. Verma, Dietrich G. Leibfried, Richard P. Mirin, Sae Woo Nam, David J. Wineland
We demonstrate superconducting nanowire single photon detectors with 76 +/- 4% system detection efficiency at a wavelength of 315 nm and an operating temperature of 3.2 K, with a background count rate below 1 count per second at saturated detection

Chained Bell inequality experiment with high-efficiency measurements

March 28, 2017
Author(s)
Ting Rei Tan, Stephen D. Erickson, Peter L. Bierhorst, Daniel Kienzler, Scott C. Glancy, Emanuel H. Knill, Dietrich G. Leibfried, David J. Wineland, Yong Wan
We report correlation measurements on two 9Be+ ions that violate a chained Bell inequality obeyed by any local-realistic theory. The correlations can be modeled as derived from a mixture of a local-realistic probabilistic distribution and a distribution

Hybrid quantum systems with trapped charged particles

February 21, 2017
Author(s)
Shlomi S. Kotler, Raymond Simmonds, Dietrich Leibfried, David J. Wineland
Trapped charged particles have been at the forefront of quantum information processing (QIP) for a few decades now, with deterministic two-qubit logic gates reaching record fidelities of 99.9% and single-qubit operations of much higher fidelity. In a

Measurements of trapped-ion heating rates with exchangeable surfaces in close proximity

January 15, 2017
Author(s)
Dustin A. Hite, Kyle S. McKay, Shlomi Salman Kotler, Dietrich G. Leibfried, David J. Wineland, David P. Pappas
Electric-field noise from the surfaces of ion-trap electrodes couples to the ion’s charge causing heating of the ion’s motional modes. This heating limits the fidelity of quantum gates implemented in quantum information processing experiments. The exact

VECSEL systems for generation and manipulation of trapped magnesium ions

November 8, 2016
Author(s)
Shaun C. Burd, David T. Allcock, Tomi Leinonen, Jussi-Pekka Penttinen, Daniel H. Slichter, Raghavendra Srinivas, Andrew C. Wilson, Robert Jordens, Micrea Guina, Dietrich G. Leibfried, David J. Wineland
Experiments in atomic, molecular, and optical (AMO) physics rely on lasers at many different wave- lengths and with varying requirements on spectral linewidth, power and intensity stability. Vertical external-cavity surface-emitting lasers (VECSELs), when

Preparation of entangled states through Hilbert space engineering

September 28, 2016
Author(s)
Yiheng Lin, John P. Gaebler, Florentin Reiter, Ting R. Tan, Ryan S. Bowler, Yong Wan, Adam C. Keith, Emanuel Knill, Kevin Coakley, Dietrich Leibfried, David J. Wineland, Scott Glancy
Entangled states are a crucial resource for quantum-based technologies such as quantum computers and quantum communication systems. Exploring new methods for entanglement generation is important for diversifying and eventually improving current approaches

High Fidelity Universal Gate Set for 9Be+ Ion Qubits

August 4, 2016
Author(s)
John P. Gaebler, Ting R. Tan, Yong Wan, Yiheng Lin, Ryan S. Bowler, Adam C. Keith, Scott Glancy, Kevin Coakley, Emanuel Knill, Dietrich Leibfried, David J. Wineland
We report high-fidelity laser-beam-induced quantum logic gates on qubits comprised of hyperfine states in 9Be+ ions, achieved in part through a combination of improved laser beam quality and control and improved state preparation. We demonstrate single

Arrays of individually controlled ions suitable for two-dimensional quantum simulations

June 13, 2016
Author(s)
Manuel Mielenz, Henning Kalis, Matthias Wittemer, Frederick Hakelberg, Roman Blain, Peter Maunz, Dietrich Leibfried, Tobias Schaetz
A custom-built and precisely controlled quantum system may o ffer access to a fundamental understanding of another, less accessible system of interest. A universal quantum computer is currently out of reach, but an analog quantum simulator (AQS) that makes