Unconventional Transport in the “Hole” Regime of a Si Double Quantum Dot

Koh, Teck Seng; Simmons, C. B.; Eriksson, M. A.; Coppersmith, S. N.; Friesen, Mark

doi:10.1103/physrevlett.106.186801

Cited by 6 publications

(10 citation statements)

References 20 publications

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“…Thus, the splittings within the triplet-like manifold are much finer than the splitting between the singlet-and triplet-like manifolds. These arguments are borne out by our calculations [15].…”

Section: Assupporting

confidence: 55%

“…Current will flow through the triplet-like channel when the loading rate is comparable to the unloading rate in the singlet-like channel [15]. In the Supplementary Information, we estimate these rates and find that they are indeed the same order of magnitude.…”

Section: Asmentioning

confidence: 79%

“…13. From the energy levels and possible transitions between states, we calculate the electrochemical potentials for charging or discharging a dot by one electron [15]. The four relevant electrochemical potentials for the dots are shown for the two-electron case in Fig.…”

Section: Asmentioning

confidence: 99%

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Unconventional Transport in the "Hole" Regime of a Si Double Quantum Dot

Koh,

Simmons,

Eriksson

et al. 2010

Preprint

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Studies of electronic charge transport through semiconductor double quantum dots rely on a conventional 'hole' model of transport in the three-electron regime. We show that experimental measurements of charge transport through a Si double quantum dot in this regime cannot be fully explained using the conventional picture. Using a Hartree-Fock (HF) formalism and relevant HF energy parameters extracted from transport data in the multiple-electron regime, we identify a novel spin-flip cotunneling process that lifts a singlet blockade.

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Section: Assupporting

confidence: 55%

Section: Asmentioning

confidence: 79%

See 1 more Smart Citation

Unconventional Transport in the "Hole" Regime of a Si Double Quantum Dot

Koh,

Simmons,

Eriksson

et al. 2010

Preprint

Self Cite

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show abstract

“…The current in the spin blockade region in Fig. 2b is not completely suppressed; in real systems, the electron spins can be mixed or flipped by the nuclear field hyperfine interaction 19,20 , spin-orbit coupling 20,21 or cotunneling 17,[21][22][23] , which generates a finite leakage current and lifts the spin blockade. This leakage can be strongly suppressed, in Fig.…”

Section: Spin Blockadementioning

confidence: 99%

Electron spin resonance and spin–valley physics in a silicon double quantum dot

et al. 2014

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Silicon quantum dots are a leading approach for solid-state quantum bits. However, developing this technology is complicated by the multi-valley nature of silicon. Here we observe transport of individual electrons in a silicon CMOS-based double quantum dot under electron spin resonance. An anticrossing of the driven dot energy levels is observed when the Zeeman and valley splittings coincide. A detected anticrossing splitting of 60 MHz is interpreted as a direct measure of spin and valley mixing, facilitated by spin-orbit interaction in the presence of non-ideal interfaces. A lower bound of spin dephasing time of 63 ns is extracted. We also describe a possible experimental evidence of an unconventional spin-valley blockade, despite the assumption of non-ideal interfaces. This understanding of silicon spin-valley physics should enable better control and read-out techniques for the spin qubits in an all CMOS silicon approach.

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“…2(d), where total spin can be conserved while the spin on the lithographic dot is flipped via exchange with an electron occupying the impurityinduced level. This behavior is closely related to processes occurring in other three-electron systems [21][22][23], including the quantum dot hybrid qubit [24].…”

mentioning

confidence: 68%

Lifting of spin blockade by charged impurities in Si-MOS double quantum dot devices

et al. 2020

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One obstacle that has slowed the development of electrically gated metal-oxide-semiconductor (MOS) singlet-triplet qubits is the frequent lack of observed spin blockade, even in samples with large singlet-triplet energy splittings. We present theoretical and experimental evidence that the cause of this problem in MOS double quantum dots is the stray positive charges in the oxide inducing accidental levels near the device's active region that allow spin blockade lifting. We also present evidence that these effects can be mitigated by device design modifications, such as overlapping gates.

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Unconventional Transport in the “Hole” Regime of a Si Double Quantum Dot

Cited by 6 publications

References 20 publications

Unconventional Transport in the "Hole" Regime of a Si Double Quantum Dot

Unconventional Transport in the "Hole" Regime of a Si Double Quantum Dot

Electron spin resonance and spin–valley physics in a silicon double quantum dot

Lifting of spin blockade by charged impurities in Si-MOS double quantum dot devices

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