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Probing low noise at the MOS interface with a spin-orbit qubit

arXiv.org

Jock, Ryan M.; Jacobson, Noah T.; Harvey-Collard, Patrick; Mounce, Andrew M.; Srinivasa, Vanita S.; Ward, Daniel R.; Anderson, John M.; Manginell, Ronald P.; Wendt, J.R.; Rudolph, Martin R.; Pluym, Tammy P.; Laros, James H.; Baczewski, Andrew D.; Witzel, Wayne W.; Carroll, Malcolm

The silicon metal-oxide-semiconductor (MOS) material system is technologically important for the implementation of electron spin-based quantum information technologies. Researchers predict the need for an integrated platform in order to implement useful computation, and decades of advancements in silicon microelectronics fabrication lends itself to this challenge. However, fundamental concerns have been raised about the MOS interface (e.g. trap noise, variations in electron g-factor and practical implementation of multi-QDs). Furthermore, two-axis control of silicon qubits has, to date, required the integration of non-ideal components (e.g. microwave strip-lines, micro-magnets, triple quantum dots, or introduction of donor atoms). In this paper, we introduce a spin-orbit (SO) driven singlet- triplet (ST) qubit in silicon, demonstrating all-electrical two-axis control that requires no additional integrated elements and exhibits charge noise properties equivalent to other more model, but less commercially mature, semiconductor systems. We demonstrate the ability to tune an intrinsic spin-orbit interface effect, which is consistent with Rashba and Dresselhaus contributions that are remarkably strong for a low spin-orbit material such as silicon. The qubit maintains the advantages of using isotopically enriched silicon for producing a quiet magnetic environment, measuring spin dephasing times of 1.6 μs using 99.95% 28Si epitaxy for the qubit, comparable to results from other isotopically enhanced silicon ST qubit systems. This work, therefore, demonstrates that the interface inherently provides properties for two-axis control, and the technologically important MOS interface does not add additional detrimental qubit noise. isotopically enhanced silicon ST qubit systems

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TYPE Journal Article YEAR 2017
OSTI

Coupling MOS quantum dot and phosphorous donor qubit systems

Technical Digest - International Electron Devices Meeting, IEDM

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, P.

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 2017
DOIDOIOSTIScopusOSTIScopus

Valley splitting of single-electron Si MOS quantum dots

Applied Physics Letters

Laros, James H.; Harvey-Collard, Patrick; Jacobson, Noah T.; Baczewski, Andrew D.; Nielsen, Erik N.; Maurer, Leon; Montano, Ines M.; Rudolph, Martin R.; Carroll, Malcolm; Yang, C.H.; Rossi, A.; Dzurak, A.S.; Muller, Richard P.

Silicon-based metal-oxide-semiconductor quantum dots are prominent candidates for high-fidelity, manufacturable qubits. Due to silicon's band structure, additional low-energy states persist in these devices, presenting both challenges and opportunities. Although the physics governing these valley states has been the subject of intense study, quantitative agreement between experiment and theory remains elusive. Here, we present data from an experiment probing the valley states of quantum dot devices and develop a theory that is in quantitative agreement with both this and a recently reported experiment. Through sampling millions of realistic cases of interface roughness, our method provides evidence that the valley physics between the two samples is essentially the same.

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TYPE Journal Article YEAR 2016
DOIOSTIScopus

Nuclear-driven electron spin rotations in a single donor coupled to a silicon quantum dot

Science

Carroll, Malcolm; Harvey-Collard, Patrick; Jacobson, Noah T.; Rudolph, Martin R.; Dominguez, Jason J.; Ten Eyck, Gregory A.; Wendt, J.R.; Pluym, Tammy P.; Laros, James H.; Lilly, Michael L.; Pioro-Ladriere, Michel

Silicon chips hosting a single donor can be used to store and manipulate one bit of quantum information. However, a central challenge for realizing quantum logic operations is to couple donors to one another in a controllable way. To achieve this, several proposals rely on using nearby quantum dots (QDs) to mediate an interaction. In this work, we demonstrate the coherent coupling of electron spins between a single 31 P donor and an enriched 28 Si metal-oxide-semiconductor few-electron QD. We show that the electron-nuclear spin interaction on the donor can drive coherent rotations between singlet and triplet electron spin states of the QD-donor system. Moreover, we are able to tune electrically the exchange interaction between the QD and donor electrons. Furthermore, the combination of single-nucleus-driven rotations and voltage-tunable exchange provides every key element for future all-electrical control of spin qubits, while requiring only a single QD and no additional magnetic field gradients

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TYPE Journal Article YEAR 2016
DOIOSTI
Results 51–75 of 96
Results 51–75 of 96