2023
|
| Omirzakhov, Kaisarbek; Idjadi, Mohamad Hossein; Huang, Tzu-Yung; Breitweiser, Alex S; Hopper, David A; Bassett, Lee C; Aflatouni, Firooz An Integrated Reconfigurable Spin Control System on 180 nm CMOS for Diamond NV Centers Journal Article IEEE Transactions on Microwave Theory and Techniques, pp. 1-12, 2023. Abstract | Links | BibTeX | Tags: diamond NV center, Quantum Control, spin readout @article{Omirzakhov2023,
title = {An Integrated Reconfigurable Spin Control System on 180 nm CMOS for Diamond NV Centers},
author = {Kaisarbek Omirzakhov and Mohamad Hossein Idjadi and Tzu-Yung Huang and S. Alex Breitweiser and David A. Hopper and Lee C. Bassett and Firooz Aflatouni},
url = {https://ieeexplore.ieee.org/document/10079193/keywords#keywords},
doi = {10.1109/TMTT.2023.3254600},
year = {2023},
date = {2023-03-23},
journal = {IEEE Transactions on Microwave Theory and Techniques},
pages = {1-12},
abstract = {Solid-state electron spins are key building blocks for emerging applications in quantum information science, including quantum computers, quantum communication links, and quantum sensors. These solid-state spins are mainly controlled using complex microwave pulse sequences, which are typically generated using benchtop electrical instruments. Integration of the required electronics will enable realization of a scalable low-power and compact optically addressable quantum system. Here, we report an integrated reconfigurable quantum control system, which is used to find electron-spin resonance (ESR) frequency and perform Rabi, Ramsey, and Hahn-echo measurements for a nitrogen-vacancy (NV) center spin qubit in diamond. The chip can be programmed to synthesize an RF signal tunable from 1.6 to 2.6 GHz, which is modulated with a sequence of up to 4098 reconfigurable pulses with a pulse width and pulse-to-pulse delay adjustable from 10 ns to 42 ms and 18 ns to 42 ms, respectively, at a resolution of 2.5 ns. The 180-nm CMOS chip is fabricated within a footprint of 3.02 mm 2 and has a power consumption of 80 mW.},
keywords = {diamond NV center, Quantum Control, spin readout},
pubstate = {published},
tppubtype = {article}
}
Solid-state electron spins are key building blocks for emerging applications in quantum information science, including quantum computers, quantum communication links, and quantum sensors. These solid-state spins are mainly controlled using complex microwave pulse sequences, which are typically generated using benchtop electrical instruments. Integration of the required electronics will enable realization of a scalable low-power and compact optically addressable quantum system. Here, we report an integrated reconfigurable quantum control system, which is used to find electron-spin resonance (ESR) frequency and perform Rabi, Ramsey, and Hahn-echo measurements for a nitrogen-vacancy (NV) center spin qubit in diamond. The chip can be programmed to synthesize an RF signal tunable from 1.6 to 2.6 GHz, which is modulated with a sequence of up to 4098 reconfigurable pulses with a pulse width and pulse-to-pulse delay adjustable from 10 ns to 42 ms and 18 ns to 42 ms, respectively, at a resolution of 2.5 ns. The 180-nm CMOS chip is fabricated within a footprint of 3.02 mm 2 and has a power consumption of 80 mW. |
2020
|
| Hopper, D A; Lauigan, J D; Huang, T -Y; Bassett, L C Real-Time Charge Initialization of Diamond Nitrogen-Vacancy Centers for Enhanced Spin Readout Journal Article Phys. Rev. Applied, 13 , pp. 024016, 2020. Abstract | Links | BibTeX | Tags: diamond NV center, spin readout @article{Hopper2019,
title = {Real-Time Charge Initialization of Diamond Nitrogen-Vacancy Centers for Enhanced Spin Readout},
author = {D A Hopper and J D Lauigan and T -Y Huang and L C Bassett},
url = {https://arxiv.org/abs/1907.08741
https://journals.aps.org/prapplied/abstract/10.1103/PhysRevApplied.13.024016
https://medium.com/penn-engineering/penn-engineers-ensure-quantum-experiments-get-off-to-the-right-start-bbe6f3382cb},
year = {2020},
date = {2020-02-07},
journal = {Phys. Rev. Applied},
volume = {13},
pages = {024016},
abstract = {Selected as an Editor's Suggestion.
A common impediment to qubit performance is imperfect state initialization. In the case of the diamond nitrogen-vacancy (NV) center, the initialization fidelity is limited by fluctuations in the defect's charge state during optical pumping. Here, we use real-time control to deterministically initialize the NV center's charge state at room temperature. We demonstrate a maximum charge initialization fidelity of 99.4±0.1% and present a quantitative model of the initialization process that allows for systems-level optimization of the spin-readout signal-to-noise ratio. Even accounting for the overhead associated with the initialization sequence, increasing the charge initialization fidelity from the steady-state value of 75% near to unity allows for a factor-of-two speedup in experiments while maintaining the same signal-to-noise-ratio. In combination with high-fidelity readout based on spin-to-charge conversion, real-time initialization enables a factor-of-20 speedup over traditional methods, resulting in an ac magnetic sensitivity of 1.3 nT/Hz1/2 for our single NV-center spin. The real-time control method is immediately beneficial for quantum sensing applications with NV centers as well as probing charge-dependent physics, and it will facilitate protocols for quantum feedback control over multi-qubit systems.},
keywords = {diamond NV center, spin readout},
pubstate = {published},
tppubtype = {article}
}
Selected as an Editor's Suggestion.
A common impediment to qubit performance is imperfect state initialization. In the case of the diamond nitrogen-vacancy (NV) center, the initialization fidelity is limited by fluctuations in the defect's charge state during optical pumping. Here, we use real-time control to deterministically initialize the NV center's charge state at room temperature. We demonstrate a maximum charge initialization fidelity of 99.4±0.1% and present a quantitative model of the initialization process that allows for systems-level optimization of the spin-readout signal-to-noise ratio. Even accounting for the overhead associated with the initialization sequence, increasing the charge initialization fidelity from the steady-state value of 75% near to unity allows for a factor-of-two speedup in experiments while maintaining the same signal-to-noise-ratio. In combination with high-fidelity readout based on spin-to-charge conversion, real-time initialization enables a factor-of-20 speedup over traditional methods, resulting in an ac magnetic sensitivity of 1.3 nT/Hz1/2 for our single NV-center spin. The real-time control method is immediately beneficial for quantum sensing applications with NV centers as well as probing charge-dependent physics, and it will facilitate protocols for quantum feedback control over multi-qubit systems. |
2018
|
| Hopper, D A; Shulevitz, H J; Bassett, L C Spin readout techniques of the nitrogen-vacancy center in diamond Journal Article Micromachines, 9 , pp. 437, 2018. Abstract | Links | BibTeX | Tags: diamond NV center, spin readout @article{Hopper2018,
title = {Spin readout techniques of the nitrogen-vacancy center in diamond},
author = {D A Hopper and H J Shulevitz and L C Bassett},
url = {https://www.mdpi.com/2072-666X/9/9/437},
year = {2018},
date = {2018-08-30},
journal = {Micromachines},
volume = {9},
pages = {437},
abstract = {The diamond nitrogen-vacancy (NV) center is a leading platform for quantum information science due to its optical addressability and room-temperature spin coherence. However, measurements of the NV center’s spin state typically require averaging over many cycles to overcome noise. Here, we review several approaches to improve the readout performance and highlight future avenues of research that could enable single-shot electron-spin readout at room temperature.},
keywords = {diamond NV center, spin readout},
pubstate = {published},
tppubtype = {article}
}
The diamond nitrogen-vacancy (NV) center is a leading platform for quantum information science due to its optical addressability and room-temperature spin coherence. However, measurements of the NV center’s spin state typically require averaging over many cycles to overcome noise. Here, we review several approaches to improve the readout performance and highlight future avenues of research that could enable single-shot electron-spin readout at room temperature. |
| Hopper, D A; Grote, R R; Parks, S M; Bassett, L C Amplified sensitivity of nitrogen-vacancy spins in nanodiamonds using all-optical charge readout Journal Article ACS Nano, 12 , pp. 4678-4686, 2018. Abstract | Links | BibTeX | Tags: diamond NV center, spin readout @article{Hopper2018b,
title = {Amplified sensitivity of nitrogen-vacancy spins in nanodiamonds using all-optical charge readout},
author = {D A Hopper and R R Grote and S M Parks and L C Bassett},
url = {https://pubs.acs.org/doi/10.1021/acsnano.8b01265
https://arxiv.org/abs/1712.03882},
year = {2018},
date = {2018-04-13},
journal = {ACS Nano},
volume = {12},
pages = {4678-4686},
abstract = {Nanodiamonds containing nitrogen-vacancy (NV) centers offer a versatile platform for sensing applications spanning from nanomagnetism to in vivo monitoring of cellular processes. In many cases, however, weak optical signals and poor contrast demand long acquisition times that prevent the measurement of environmental dynamics. Here, we demonstrate the ability to perform fast, high-contrast optical measurements of charge distributions in ensembles of NV centers in nanodiamonds and use the technique to improve the spin-readout signal-to-noise ratio through spin-to-charge conversion. A study of 38 nanodiamonds with sizes ranging between 20 and 70 nm, each hosting a small ensemble of NV centers, uncovers complex, multiple time scale dynamics due to radiative and nonradiative ionization and recombination processes. Nonetheless, the NV-containing nanodiamonds universally exhibit charge-dependent photoluminescence contrasts and the potential for enhanced spin readout using spin-to-charge conversion. We use the technique to speed up a T1 relaxometry measurement by a factor of 5.},
keywords = {diamond NV center, spin readout},
pubstate = {published},
tppubtype = {article}
}
Nanodiamonds containing nitrogen-vacancy (NV) centers offer a versatile platform for sensing applications spanning from nanomagnetism to in vivo monitoring of cellular processes. In many cases, however, weak optical signals and poor contrast demand long acquisition times that prevent the measurement of environmental dynamics. Here, we demonstrate the ability to perform fast, high-contrast optical measurements of charge distributions in ensembles of NV centers in nanodiamonds and use the technique to improve the spin-readout signal-to-noise ratio through spin-to-charge conversion. A study of 38 nanodiamonds with sizes ranging between 20 and 70 nm, each hosting a small ensemble of NV centers, uncovers complex, multiple time scale dynamics due to radiative and nonradiative ionization and recombination processes. Nonetheless, the NV-containing nanodiamonds universally exhibit charge-dependent photoluminescence contrasts and the potential for enhanced spin readout using spin-to-charge conversion. We use the technique to speed up a T1 relaxometry measurement by a factor of 5. |
2016
|
| Hopper, D A; Grote, R R; Exarhos, A L; Bassett, L C Near-infrared-assisted charge control and spin readout of the nitrogen-vacancy center in diamond Journal Article Physical Review B, 94 , pp. 241201, 2016. Abstract | Links | BibTeX | Tags: diamond NV center, spin readout @article{Hopper2016,
title = {Near-infrared-assisted charge control and spin readout of the nitrogen-vacancy center in diamond},
author = {D A Hopper and R R Grote and A L Exarhos and L C Bassett},
url = {https://journals.aps.org/prb/abstract/10.1103/PhysRevB.94.241201},
year = {2016},
date = {2016-12-09},
journal = {Physical Review B},
volume = {94},
pages = {241201},
abstract = {We utilize nonlinear absorption to design all-optical protocols that improve both charge-state initialization and spin readout for the nitrogen-vacancy (NV) center in diamond. Nonmonotonic variations in the equilibrium charge state as a function of visible and near-infrared optical power are attributed to competing multiphoton absorption processes. In certain regimes, multicolor illumination enhances the steady-state population of the NV's negative charge state above 90%. At higher NIR intensities, selective ionization of the singlet manifold facilitates a protocol for spin-to-charge conversion that dramatically enhances the spin readout fidelity. We demonstrate a sixfold increase in the signal-to-noise ratio for single-shot spin measurements and demonstrate a pathway towards single-shot electron spin readout at room temperature.},
keywords = {diamond NV center, spin readout},
pubstate = {published},
tppubtype = {article}
}
We utilize nonlinear absorption to design all-optical protocols that improve both charge-state initialization and spin readout for the nitrogen-vacancy (NV) center in diamond. Nonmonotonic variations in the equilibrium charge state as a function of visible and near-infrared optical power are attributed to competing multiphoton absorption processes. In certain regimes, multicolor illumination enhances the steady-state population of the NV's negative charge state above 90%. At higher NIR intensities, selective ionization of the singlet manifold facilitates a protocol for spin-to-charge conversion that dramatically enhances the spin readout fidelity. We demonstrate a sixfold increase in the signal-to-noise ratio for single-shot spin measurements and demonstrate a pathway towards single-shot electron spin readout at room temperature. |
2014
|
| Bassett, L C; Heremans, F J; Christle, D J; Yale, C G; Burkard, G; Buckley, B B; Awschalom, D D Ultrafast optical control of orbital and spin dynamics in a solid-state defect Journal Article Science, 345 , pp. 1333-1337, 2014. Abstract | Links | BibTeX | Tags: Condensed Matter, point defects, spin readout @article{Bassett2014,
title = {Ultrafast optical control of orbital and spin dynamics in a solid-state defect},
author = {L C Bassett and F J Heremans and D J Christle and C G Yale and G Burkard and B B Buckley and D D Awschalom},
url = {https://science.sciencemag.org/content/345/6202/1333},
year = {2014},
date = {2014-09-12},
journal = {Science},
volume = {345},
pages = {1333-1337},
abstract = {Atom-scale defects in semiconductors are promising building blocks for quantum devices, but our understanding of their material-dependent electronic structure, optical interactions, and dissipation mechanisms is lacking. Using picosecond resonant pulses of light, we study the coherent orbital and spin dynamics of a single nitrogen-vacancy center in diamond over time scales spanning six orders of magnitude. We develop a time-domain quantum tomography technique to precisely map the defect’s excited-state Hamiltonian and exploit the excited-state dynamics to control its ground-state spin with optical pulses alone. These techniques generalize to other optically addressable nanoscale spin systems and serve as powerful tools to characterize and control spin qubits for future applications in quantum technology.},
keywords = {Condensed Matter, point defects, spin readout},
pubstate = {published},
tppubtype = {article}
}
Atom-scale defects in semiconductors are promising building blocks for quantum devices, but our understanding of their material-dependent electronic structure, optical interactions, and dissipation mechanisms is lacking. Using picosecond resonant pulses of light, we study the coherent orbital and spin dynamics of a single nitrogen-vacancy center in diamond over time scales spanning six orders of magnitude. We develop a time-domain quantum tomography technique to precisely map the defect’s excited-state Hamiltonian and exploit the excited-state dynamics to control its ground-state spin with optical pulses alone. These techniques generalize to other optically addressable nanoscale spin systems and serve as powerful tools to characterize and control spin qubits for future applications in quantum technology. |