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Quantum Sensing using a Qubit for the Detection of Ionizing Radiation

Proceedings of SPIE - The International Society for Optical Engineering

Freeman, Matthew L.; Del Skinner Ramos, Suelicarmen; Lewis, Rupert M.; Carr, Stephen M.

Quantum sensing utilizes the inherent sensitivity of a quantum system to external stimuli. Our goal is to leverage this sensitivity to develop a quantum sensor designed for the detection of ionizing radiation. Here we report on the design, fabrication, and measurement of a new quantum device for hard x-ray and gamma-ray detection. Our quantum device is based on a superconducting quantum bit (qubit) with superconducting tunnel junctions as the core device elements. We describe our experimental investigation directed toward the detection metrics of energy resolution, dynamic range, and active area. In contrast to existing superconducting detectors, the active area per qubit may be much larger than the physical area of the tunnel junctions or the physical area of the qubit device, due to the sensitivity of quantum coherence to ionizing radiation deposition within a radius on the millimeter or centimeter scale. Our experimental design enables an ionizing radiation source at room temperature to be detected by our quantum sensor at low temperature.

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TYPE Presentation YEAR 2024
DOIOSTIScopus

FAIR DEAL Grand Challenge Overview

Allemang, Christopher R.; Anderson, Evan M.; Baczewski, Andrew D.; Bussmann, Ezra; Butera, Robert; Campbell, Deanna M.; Campbell, Quinn; Carr, Stephen M.; Frederick, Esther; Gamache, Phillip; Gao, Xujiao; Grine, Albert; Gunter, Mathew; Halsey, Connor; Ivie, Jeffrey A.; Katzenmeyer, Aaron M.; Leenheer, Andrew J.; Lepkowski, William; Lu, Tzu M.; Mamaluy, Denis; Mendez Granado, Juan P.; Pena, Luis F.; Schmucker, Scott W.; Scrymgeour, David; Tracy, Lisa A.; Wang, George T.; Ward, Dan; Young, Steve M.

While it is likely practically a bad idea to shrink a transistor to the size of an atom, there is no arguing that it would be fantastic to have atomic-scale control over every aspect of a transistor – a kind of crystal ball to understand and evaluate new ideas. This project showed that it was possible to take a niche technique used to place dopants in silicon with atomic precision and apply it broadly to study opportunities and limitations in microelectronics. In addition, it laid the foundation to attaining atomic-scale control in semiconductor manufacturing more broadly.

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TYPE SAND Report YEAR 2021
DOIOSTI

Quantum dots with split enhancement gate tunnel barrier control

Applied Physics Letters

Rochette, S.; Rudolph, Martin; Roy, A.M.; Curry, Matthew; Eyck, G.A.T.; Manginell, Ronald; Wendt, Joel R.; Pluym, Tammy; Carr, Stephen M.; Ward, Daniel R.; Lilly, M.P.; Carroll, M.S.

We introduce a silicon metal-oxide-semiconductor quantum dot architecture based on a single polysilicon gate stack. The elementary structure consists of two enhancement gates separated spatially by a gap, one gate forming a reservoir and the other a quantum dot. We demonstrate that, in three devices based on two different versions of this elementary structure, a wide range of tunnel rates is attainable while maintaining single-electron occupation. A characteristic change in the slope of the charge transitions as a function of the reservoir gate voltage, attributed to screening from charges in the reservoir, is observed in all devices and is expected to play a role in the sizable tuning orthogonality of the split enhancement gate structure. The all-silicon process is expected to minimize strain gradients from electrode thermal mismatch, while the single gate layer should avoid issues related to overlayers (e.g., additional dielectric charge noise) and help improve the yield. Finally, reservoir gate control of the tunnel barrier has implications for initialization, manipulation, and readout schemes in multi-quantum dot architectures.

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TYPE Journal Article YEAR 2019
DOIOSTIScopus

Spectroscopy of Multielectrode Tunnel Barriers

Physical Review Applied

Carroll, M.S.; Shirkhorshidian, Amir; Gamble, John K.; Maurer, Leon; Carr, Stephen M.; Dominguez, Jason; Ten Eyck, Gregory A.; Wendt, Joel R.; Nielsen, Erik N.; Jacobson, Noah T.; Lilly, Michael

Despite their ubiquity in nanoscale electronic devices, the physics of tunnel barriers has not been developed to the extent necessary for the engineering of devices in the few-electron regime. This problem is of urgent interest, as this is the specific regime into which current extreme-scale electronics fall. Here, we propose theoretically and validate experimentally a compact model for multielectrode tunnel barriers, suitable for design-rules-based engineering of tunnel junctions in quantum devices. We perform transport spectroscopy at approximately T=4 K, extracting effective barrier heights and widths for a wide range of biases, using an efficient Landauer-Büttiker tunneling model to perform the analysis. We find that the barrier height shows several regimes of voltage dependence, either linear or approximately exponential. Effects on threshold, such as metal-insulator transition and lateral confinement, are included because they influence parameters that determine barrier height and width (e.g., the Fermi energy and local electric fields). We compare these results to semiclassical solutions of Poisson's equation and find them to agree qualitatively. Finally, this characterization technique is applied to an efficient lateral tunnel barrier design that does not require an electrode directly above the barrier region in order to estimate barrier heights and widths.

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TYPE Journal Article YEAR 2018
DOIOSTIScopus

Single-electron-occupation metal-oxide-semiconductor quantum dots formed from efficient poly-silicon gate layout

Physical Review Applied

Carroll, M.S.; Rochette, Sophie; Rudolph, Martin; Roy, A.M.; Curry, Matthew; Ten Eyck, Gregory A.; Manginell, Ronald; Wendt, Joel R.; Pluym, Tammy; Carr, Stephen M.; Ward, Daniel R.; Lilly, Michael; Pioro-Ladriere, Michel

We introduce a silicon metal-oxide-semiconductor quantum dot structure that achieves dot-reservoir tunnel coupling control without a dedicated barrier gate. The elementary structure consists of two accumulation gates separated spatially by a gap, one gate accumulating a reservoir and the other a quantum dot. Control of the tunnel rate between the dot and the reservoir across the gap is demonstrated in the single electron regime by varying the reservoir accumulation gate voltage while compensating with the dot accumulation gate voltage. The method is then applied to a quantum dot connected in series to source and drain reservoirs, enabling transport down to the single electron regime. Finally, tuning of the valley splitting with the dot accumulation gate voltage is observed. This split accumulation gate structure creates silicon quantum dots of similar characteristics to other realizations but with less electrodes, in a single gate stack subtractive fabrication process that is fully compatible with silicon foundry manufacturing.

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TYPE Journal Article YEAR 2017
OSTI

Single shot spin readout with a cryogenic high-electron-mobility transistor amplifier at sub-Kelvin temperatures

Applied Physics Letters

Tracy, Lisa A.; Luhman, Dwight R.; Carr, Stephen M.; Bishop, Nathaniel C.; Ten Eyck, Gregory A.; Pluym, Tammy; Wendt, Joel R.; Lilly, Michael; Carroll, M.S.

We use a cryogenic high-electron-mobility transistor circuit to amplify the current from a single electron transistor, allowing for demonstration of single shot readout of an electron spin on a single P donor in Si with 100 kHz bandwidth and a signal to noise ratio of ~9. In order to reduce the impact of cable capacitance, the amplifier is located adjacent to the Si sample, at the mixing chamber stage of a dilution refrigerator. For a current gain of ~2.7 x 103 the power dissipation of the amplifier is 13 μW, the bandwidth is ~1.3 MHz, and for frequencies above 300 kHz the current noise referred to input is ≤ 70 fA/√Hz. Furthermore, with this amplification scheme, we are able to observe coherent oscillations of a P donor electron spin in isotopically enriched 28Si with 96% visibility.

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TYPE Journal Article YEAR 2016
DOIOSTI

Cryogenic Preamplification of a Single-Electron-Transistor using a Silicon-Germanium Heterojunction-Bipolar-Transistor

Applied Physics Letters

Curry, Matthew J.; England, Troy D.; Bishop, Nathaniel; Ten Eyck, Gregory A.; Wendt, Joel R.; Pluym, Tammy; Lilly, Michael; Carr, Stephen M.; Carroll, M.S.

We examine a silicon-germanium heterojunction bipolar transistor (HBT) for cryogenic pre-amplification of a single electron transistor (SET). The SET current modulates the base current of the HBT directly. The HBT-SET circuit is immersed in liquid helium, and its frequency response from low frequency to several MHz is measured. The current gain and the noise spectrum with the HBT result in a signal-to-noise-ratio (SNR) that is a factor of 10–100 larger than without the HBT at lower frequencies. Furthermore, the transition frequency defined by SNR = 1 has been extended by as much as a factor of 10 compared to without the HBT amplification. The power dissipated by the HBT cryogenic pre-amplifier is approximately 5 nW to 5 μW for the investigated range of operation. We found that the circuit is also operated in a single electron charge read-out configuration in the time-domain as a proof-of-principle demonstration of the amplification approach for single spin read-out.

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TYPE Journal Article YEAR 2015
DOIOSTI
62 Results
62 Results