Quantum Computing & Sensing
CIPHER’s Quantum Systems Division (QSD) investigates quantum computing systems based on individual trapped atomic ions and novel quantum sensor devices based on atomic systems. QSD has designed, fabricated, and demonstrated a number of ion traps and state-of-the-art components to support integrated quantum information systems. Current efforts focus on implementing small quantum algorithms in these devices with the goal of better understanding the effects of noise on fidelity of the algorithms. Additional topics of investigation include chip-scale atomic magnetometers, atomic clocks, cold-atom gyroscopes, and quantum-secured communications.
Publications
Transport-Enabled Entangling Gate for Trapped Ions
H.N. Tinkey, C.R. Clark, B.C. Sawyer, and K.R. Brown
Phys. Rev. Lett. 128, 050502 (2022)
Second-Scale 9Be+ Spin Coherence in a Compact Penning Trap
B. J. McMahon and B.C. Sawyer
Phys. Rev. Applied 17, 014005 (2022)
High-fidelity Bell-state preparation with 40Ca+ optical qubits
C.Clark, H.N. Tinkey, B.C. Sawyer, A.M. Meier, K.A. Burkhardt, C.M. Seck, C.M. Shappert,
N.D. Guise, C.E. Volin, S.D. Fallek, H.T. Hayden, W.G. Rellergert, K.R. Brown,
Phys. Rev. Lett. 127, 130505 (2021)
Quantum Process Tomography of a Mølmer-Sørensen Gate via a Global Beam
H. N. Tinkey, A. M. Meier, C. R. Clark, C. M. Seck, and K. R. Brown,
Quantum Sci. Technol. 6, 034013 (2021).
Wavelength-Insensitive, Multispecies Entangling Gate for Group-2 Atomic Ions
B. C. Sawyer and K. R. Brown, Phys. Rev. A 103, 022427 (2021).

Bridging Classical and Quantum with SDP Initialized Warm-Starts for QAOA
R. Tate, M. Farhadi, C. Herold, G. Mohler, and S. Gupta,
ArXiv:2010.14021 [Quant- Ph] (2020).
Single-Ion Addressing via Trap Potential Modulation in Global Optical Fields
C. M. Seck, A. M. Meier, J. T. Merrill, H. T. Hayden, B. C. Sawyer, C. E. Volin, and
K. R. Brown, New J. Phys. 22, 053024 (2020).
Generating Target Graph Couplings for QAOA from Native Quantum Hardware Couplings
J. Rajakumar, J. Moondra, S. Gupta, and C. D. Herold, ArXiv:2011.08165 [Physics, Physics:Quant-Ph] (2020).
All-Optical Intrinsic Atomic Gradiometer with Sub-20 fT/Hz^0.5 sensitivity in a 22 uT
Earth-Scale Magnetic Field
A. R. Perry, M. D. Bulatowicz, M. D. Bulatowicz, M. Larsen, T. G. Walker, and R. Wyllie,
Opt. Express, OE 28, 36696 (2020).
Doppler-Cooled Ions in a Compact Reconfigurable Penning Trap
B. J. McMahon, C. Volin, W. G. Rellergert, and B. C. Sawyer, Phys. Rev. A 101, 013408 (2020).
Testing the Robustness of Robust Phase Estimation
A. M. Meier, K. A. Burkhardt, B. J. McMahon, and C. D. Herold, Rev. A 100, 052106 (2019).
Scalable Ion–Photon Quantum Interface Based on Integrated Diffractive Mirrors
M. Ghadimi, V. Blūms, B. G. Norton, P. M. Fisher, S. C. Connell, J. M. Amini, C. Volin,
H. Hayden, C.-S. Pai, D. Kielpinski, M. Lobino, and E. W. Streed,
Npj Quantum Information 3, 4 (2017).
Universal Control of Ion Qubits in a Scalable Microfabricated Planar Trap
C. D. Herold, S. D. Fallek, J. T. Merrill, A. M. Meier, K. R. Brown, C. E. Volin, and J. M. Amini, New J. Phys. 18, 023048 (2016).
Transport Implementation of the Bernstein–Vazirani Algorithm with Ion Qubits
S. D. Fallek, C. D. Herold, B. J. McMahon, K. M. Maller, K. R. Brown, and J. M. Amini,
New J. Phys. 18, 083030 (2016).
Ball-Grid Array Architecture for Microfabricated Ion Traps
N. D. Guise, S. D. Fallek, K. E. Stevens, K. R. Brown, C. Volin, A. W. Harter, J. M. Amini,
R. E. Higashi, S. T. Lu, H. M. Chanhvongsak, T. A. Nguyen, M. S. Marcus, T. R. Ohnstein, and
D. W. Youngner, Journal of Applied Physics 117, 174901 (2015).
Modulating Carrier and Sideband Coupling Strengths in a Standing-Wave Gate Beam
T. E. deLaubenfels, K. A. Burkhardt, G. Vittorini, J. T. Merrill, K. R. Brown, and J. M. Amini,
JPhys. Rev. A 92, 061402 (2015).
In-Vacuum Active Electronics for Microfabricated Ion Traps
N. D. Guise, S. D. Fallek, H. Hayden, C.-S. Pai, C. Volin, K. R. Brown, J. T. Merrill, A. W.
Harter, J. M. Amini, L. M. Lust, K. Muldoon, D. Carlson, and J. Budach,
Review of Scientific Instruments 85, 063101 (2014).