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Search Publications by

John J. Bollinger (Fed)

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Displaying 1 - 25 of 129

Quantum-enhanced sensing of displacements and electric fields with large trapped-ion crystals

August 6, 2021
Kevin Gilmore, Matthew Affolter, Judith Jordan, Diego Barberena, Robert Lewis-Swan, Ana Maria Rey, John Bollinger
Developing the isolation and control of ultracold atomic systems to the level of single quanta has led to significant advances in quantum sensing, yet demonstrating a quantum advantage in real world applications by harnessing entanglement remains a core

Quantum amplification of boson-mediated interactions

May 13, 2021
Shaun C. Burd, Raghavendra Srinivas, Hannah M. Knaack, Wenchao Ge, Andrew C. Wilson, David J. Wineland, Dietrich Leibfried, John J. Bollinger, David T. Allcock, Daniel Slichter
Strong and precisely controlled interactions between quantum objects are essential for quantum information processing\citeSackett2000,Majer2007}, simulation\citeBritton2012}, and sensing\citeHosten2016a,Cox2016}, and for the formation of exotic quantum

Phase-coherent sensing of the center-of-mass motion of trapped-ion crystals

November 9, 2020
Matthew Affolter, Kevin Gilmore, Elena Jordan, John Bollinger
Measurements of the center-of-mass motion of a trapped-ion crystal that are phase- coherent with an external force are reported. These experiments are conducted far from the trap motional frequency on a two-dimensional trapped ion crystal of approximately

Broadening of the drumhead mode spectrum due to in-plane thermal fluctuations of two-dimensional trapped-ion crystals in a Penning trap

November 5, 2020
Athreya Shankar, Chen Tang, Matthew Affolter, Kevin Gilmore, Daniel H. Dubin, Scott E. Parker, Murray Holland, John Bollinger
Two-dimensional crystals of ions stored in Penning traps are a leading platform for quantum simulation and sensing experiments. For small amplitudes, the out-of-plane motion of such crystals, which is exploited for quantum information protocols, can be

Generating GHZ states with squeezing and post-selection

June 1, 2020
Byron Alexander, Hermann Uys, John Bollinger
Many quantum state preparation methods rely on a combination of dissipative quantum state initialization, followed by unitary evolution to a desired target state. Here we demonstrate the usefulness of quantum measurement as an additional tool for quantum

A stroboscopic approach to trapped-ion quantum information processing with squeezed phonons

October 24, 2019
Wenchao Ge, Brian C. Sawyer, Joseph W. Britton, Kurt Jacobs, Michael Foss-Feig, John Bollinger
In trapped-ion quantum information processing, interactions between spins (qubits) are mediated by collective modes of motion of an ion crystal. While there are many different experimental strategies to design such interactions, they all face both

Quantum amplification of motion of a mechanical oscillator

June 21, 2019
Shaun C. Burd, Raghavendra Srinivas, John J. Bollinger, Andrew C. Wilson, David J. Wineland, Dietrich G. Leibfried, Daniel H. Slichter, David T. Allcock
Detection of the weakest forces in nature and the search for new physics demand increasingly sensitive measurements of the motion of mechanical oscillators. However, the attainable knowledge of an oscillator’s motion is limited by quantum fluctuations that

Near ground-state cooling of two-dimensional trapped-ion crystals with more than 100 ions

February 7, 2019
Judith Elena Jordan, Kevin A. Gilmore, Athreya Shankar, Arghavan Safari-Naini, Justin G. Bohnet, Murray Holland, John J. Bollinger
We study, both experimentally and theoretically, electromagnetically induced transparency cooling of the axial drumhead modes of 2-dimensional arrays with up to N 190 Be+ ions stored in a Penning trap. Substantial sub-Doppler cooling is observed for all N

Trapped Ion Quantum Information Processing with Squeezed Phonons

January 24, 2019
Wenchao Ge, Brian Sawyer, Joseph W. Britton, Kurt Jacobs, John Bollinger, Michael Foss-Feig
Trapped ions offer a pristine platform for quantum computation and simulation, but improving their coherence remains a crucial challenge. Here, we propose and analyze a new strategy to enhance the coherent interactions in trapped-ion systems via parametric

Verification of a Many-Ion Simulator of the Dicke Model Through Slow Quenches across a Phase Transition

July 27, 2018
Arghavan Safavi-Naini, R. J. Lewis-Swan, Justin G. Bohnet, M. Garttner, Kevin Gilmore, Elena Jordan, J. Cohn, James K. Freericks, Ana Maria Rey, John Bollinger
We use a self-assembled two-dimensional Coulomb crystal of ∼70 ions in the presence of an external transverse field to engineer a simulator of the Dicke Hamiltonian, an iconic model in quantum optics which features a quantum phase transition between a

Bang-bang shortcut to adiabaticity in the Dicke model as realized in a Penning trap experiment

May 29, 2018
J. Cohn, Arghavan Safari-Naini, R. J. Lewis-Swan, Justin G. Bohnet, M. Garttner, Kevin Gilmore, Elena Jordan, Ana Maria Rey, John Bollinger, James K. Freericks
We introduce a bang-bang shortcut to adiabaticity for the Dicke model, which we implement via a two-dimensional array of trapped ions in a Penning trap with a spin-dependent force detuned close to the center-of-mass drumhead mode. Our focus is on employing

Vibration-induced field fluctuations in a superconducting magnet

June 27, 2016
Joseph W. Britton, John J. Bollinger, Justin G. Bohnet, Brian C. Sawyer, Hermann Uys, Michael Biercuk
Superconducting magnets enable precise control of nuclear and electron spins, and are used in experiments that explore biological and condensed matter systems, and fundamental atomic particles. In high-precision applications, a common view is that that

Quantum spin dynamics and entanglement generation with hundreds of trapped ions

June 15, 2016
Justin G. Bohnet, Brian C. Sawyer, Joseph W. Britton, Michael L. Wall, A M. Rey, Michael S. Foss-Feig, John J. Bollinger
Quantum simulation of spin models can provide insights into a variety of hard problems, including the competition between entanglement and decoherence in open quantum systems. Trapped ions are an established platform for quantum simulation, but only

"Perpendicular laser cooling with a rotating wall potential in a Penning trap"

April 26, 2016
Joseph W. Britton, Justin G. Bohnet, John Bollinger, Steven B. Torrisi
We investigate the impact of a rotating wall potential on perpendicular laser cooling in a Penning ion trap. By including energy exchange with the rotating wall, we extend previous Doppler laser cooling theory and show that low perpendicular temperatures

Prospects for atomic clocks based on large ion crystals.

September 8, 2015
John J. Bollinger, Kyle Arnold, Elnur Haciyev, Chern Hui Lee, Eduardo Paez, M. D. Barrett
We investigate the feasibility of precision frequency metrology with large ion crystals. For clock candidates with a negative differential static polarisability, we show that micromotion effects should not impede the performance of the clock. Using Lu+ as

Reversing hydride-ion formation in quantum-information experiments with Be+

January 12, 2015
Brian C. Sawyer, Justin G. Bohnet, Joseph W. Britton, John J. Bollinger
We demonstrate photodissociation of BeH+ ions within a Coulomb crystal of thousands of 9Be+ confined in a Penning trap. The BeH+ molecular ions form via exothermic reactions between trapped, laser-cooled Be+($^2\text{P}_{3/2}$) and background H2 within the

Quantum simulation and many-body physics with hundreds of trapped ions

September 14, 2013
John J. Bollinger, Joseph W. Britton, Brian C. Sawyer
By employing forces that depend on the internal electronic state (or spin) of an atomic ion, the Coulomb potential energy of a trapped ion crystal can be modified in a spin-dependent way to mimic effective quantum spin Hamiltonians. We use simple models to

Relaxation timescales and decay of correlations in a long-range interacting quantum simulator

August 2, 2013
John J. Bollinger, Mauritz van den Worm, Rytis Paskauskas, Brian C. Sawyer, Michael Kastner
When a physical system is coupled to a heat bath, one expects to observe thermalization to an equilibrium state whose temperature is determined by the bath properties. For an isolated many-body system, i.e. in the absence of a heat bath, the situation is

Simulating Quantum Magnetism with Correlated Non-Neutral Ion Plasmas

August 27, 2012
John J. Bollinger, Joseph W. Britton, Brian C. Sawyer
By employing forces which depend on the internal atomic state (or spin) of an atomic ion, the Coulomb potential energy of a strongly coupled array of ions can be modified in a spin-dependent way to mimic effective quantum spin Hamiltonians. Both