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All-electrical universal control of a double quantum dot qubit in silicon MOS

Technical Digest - International Electron Devices Meeting, IEDM

Harvey-Collard, Patrick; Jock, Ryan M.; Jacobson, Noah T.; Baczewski, Andrew D.; Mounce, Andrew M.; Curry, Matthew J.; Ward, Daniel R.; Anderson, John M.; Manginell, Ronald P.; Wendt, J.R.; Rudolph, Martin R.; Pluym, Tammy P.; Lilly, Michael L.; Pioro-Ladrière, Michel; Carroll, Malcolm

Qubits based on transistor-like Si MOS nanodevices are promising for quantum computing. In this work, we demonstrate a double quantum dot spin qubit that is all-electrically controlled without the need for any external components, like micromagnets, that could complicate integration. Universal control of the qubit is achieved through spin-orbit-like and exchange interactions. Using single shot readout, we show both DC- and AC-control techniques. The fabrication technology used is completely compatible with CMOS.

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TYPE Conference Poster YEAR 2018
ScopusOSTI

Combining dynamical decoupling with optimal control for improved QIP

Carroll, Malcolm; Witzel, Wayne W.

Constructing high-fidelity control pulses that are robust to control and system/environment fluctuations is a crucial objective for quantum information processing (QIP). We combine dynamical decoupling (DD) with optimal control (OC) to identify control pulses that achieve this objective numerically. Previous DD work has shown that general errors up to (but not including) third order can be removed from {pi}- and {pi}/2-pulses without concatenation. By systematically integrating DD and OC, we are able to increase pulse fidelity beyond this limit. Our hybrid method of quantum control incorporates a newly-developed algorithm for robust OC, providing a nested DD-OC approach to generate robust controls. Motivated by solid-state QIP, we also incorporate relevant experimental constraints into this DD-OC formalism. To demonstrate the advantage of our approach, the resulting quantum controls are compared to previous DD results in open and uncertain model systems.

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TYPE Conference YEAR 2010
OSTI

Coupling MOS quantum dot and phosphorous donor qubit systems

Technical Digest - International Electron Devices Meeting, IEDM

Rudolph, Martin R.; Harvey-Collard, P.; Jock, R.; Jacobson, Noah T.; Wendt, J.R.; Pluym, Tammy P.; Dominguez, Jason J.; Ten Eyck, Gregory A.; Manginell, Ronald P.; Lilly, M.P.; Carroll, Malcolm

Si-MOS based QD qubits are attractive due to their similarity to the current semiconductor industry. We introduce a highly tunable MOS foundry compatible qubit design that couples an electrostatic quantum dot (QD) with an implanted donor. We show for the first time coherent two-axis control of a two-electron spin logical qubit that evolves under the QD-donor exchange interaction and the hyperfine interaction with the donor nucleus. The two interactions are tuned electrically with surface gate voltages to provide control of both qubit axes. Qubit decoherence is influenced by charge noise, which is of similar strength as epitaxial systems like GaAs and Si/SiGe.

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TYPE Conference Poster YEAR 2017
ScopusOSTIDOI

Coupling MOS quantum dot and phosphorous donor qubit systems

IEEE International Electron Devices Meeting

Rudolph, Martin R.; Jock, Ryan M.; Jacobson, Noah T.; Wendt, J.R.; Pluym, Tammy P.; Dominguez, Jason J.; Ten Eyck, Gregory A.; Manginell, Ronald P.; Lilly, Michael L.; Carroll, Malcolm; Harvey-Collard, Patrick H.

Si-MOS based QD qubits are attractive due to their similarity to the current semiconductor industry. We introduce a highly tunable MOS foundry compatible qubit design that couples an electrostatic quantum dot (QD) with an implanted donor. We show for the first time coherent two-axis control of a two-electron spin logical qubit that evolves under the QD-donor exchange interaction and the hyperfine interaction with the donor nucleus. The two interactions are tuned electrically with surface gate voltages to provide control of both qubit axes. Qubit decoherence is influenced by charge noise, which is of similar strength as epitaxial systems like GaAs and Si/SiGe.

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TYPE Journal Article YEAR 2016
OSTIDOI

Excited states and valley effects in a negatively charged impurity in a silicon FinFET

Rahman, Rajib R.; Muller, Richard P.; Carroll, Malcolm

The observation and characterization of a single atom system in silicon is a significant landmark in half a century of device miniaturization, and presents an important new laboratory for fundamental quantum and atomic physics. We compare with multi-million atom tight binding (TB) calculations the measurements of the spectrum of a single two-electron (2e) atom system in silicon - a negatively charged (D-) gated Arsenic donor in a FinFET. The TB method captures accurate single electron eigenstates of the device taking into account device geometry, donor potentials, applied fields, interfaces, and the full host bandstructure. In a previous work, the depths and fields of As donors in six device samples were established through excited state spectroscopy of the D0 electron and comparison with TB calculations. Using self-consistent field (SCF) TB, we computed the charging energies of the D- electron for the same six device samples, and found good agreement with the measurements. Although a bulk donor has only a bound singlet ground state and a charging energy of about 40 meV, calculations show that a gated donor near an interface can have a reduced charging energy and bound excited states in the D- spectrum. Measurements indeed reveal reduced charging energies and bound 2e excited states, at least one of which is a triplet. The calculations also show the influence of the host valley physics in the two-electron spectrum of the donor.

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TYPE Conference YEAR 2010
OSTI
Results 1–50 of 109
Results 1–50 of 109