REVIEW 6 cited by
Mapping g-factors and complex intervalley coupling in Si/SiGe by conveyor-mode shuttling
Not yet reviewed by Pith; the record is open.
This paper has not been read by Pith yet. Machine review is queued; the pith claim, tier, and objections will appear here once it completes.
SPECIMEN: schema-true, not a live event
T0 review · schema-true
One-sentence machine reading of the paper's core claim.
pith:XXXXXXXX · record.json · timestamp
Mapping g-factors and complex intervalley coupling in Si/SiGe by conveyor-mode shuttling
read the original abstract
As silicon spin qubit chips are increasing in qubit number and area, methods for the screening of qubit related material parameters become vital. Here we demonstrate the two-dimensional mapping of small variations of the electron g-factor of quantum dots formed in planar Si/SiGe quantum wells with precision better than $10^{-3}$ and with nanometer lateral resolution. We scan the electron g-factor across a 40 nm $\times$ 400 nm area and observe two g-factors per QD site which obey a striking symmetry and bimodal distribution across the area. These two g-factors relate to valley states of the electron in the quantum dot in agreement with a recent theoretical model. Using conveyor-belt shuttling of entangled electron spin pairs, complementary to the mapping of the local valley-splitting, we map the g-factor. We compare g-factor and valley splitting maps measured on the same device, and extract the complex intervalley coupling parameter along the shuttle trajectories applying a theoretical model of g-factor dependence on intervalley coupling. These maps will allow unprecedented insights into the spin-valley dynamics during qubit manipulation, readout and shuttling and serve as a benchmark for the engineering of Si/SiGe heterostructures for large-scale quantum chips.
Forward citations
Cited by 6 Pith papers
-
Valley-Aware Optimal Control of Spin Shuttling Using Cryogenic Integrated Electronics
A valley-aware co-simulation and noise-aware optimization of discrete cryogenic circuit settings achieves 99.99% average shuttling fidelity over 10 μm at 20 m/s with tens of μW power.
-
Spin Qubit Leapfrogging: Dynamics of shuttling electrons on top of another
Mobile spin qubits in silicon can leapfrog over occupied dots by exploiting low valley splitting, enabling new connectivity routes and SWAP^γ entangling gates.
-
High-fidelity EDSR in Si/SiGe Wiggle Wells
Alloy disorder in wiggle wells both randomizes and enables EDSR, with sweet spots permitting high-fidelity Rabi oscillations despite charge noise.
-
Smooth velocity shuttling for suppressing valley excitations in disordered Si/SiGe quantum dots
A Tukey-window-based smooth velocity shuttling protocol reduces valley excitations and average spin infidelity in disordered Si/SiGe quantum dots via analytical design and statistical simulations.
-
Sharp periodic Ge concentration modulations beyond the conduction band valley wavevector $k_0$ in nuclear spin-free Si quantum wells
Experimental demonstration of Ge concentration modulations in Si quantum wells with periods from 2.00 nm to 0.49 nm (including at k0 and 2k0/3), characterized by X-ray and STEM showing high homogeneity and gradients u...
-
Singlet-triplet oscillations in multivalley Si double quantum dots
Theoretical expressions for singlet return probability in multivalley Si double quantum dots near spin-valley resonances are derived, accounting for valley occupations, and validated against experiments to map valley ...
discussion (0)
Sign in with ORCID, Apple, or X to comment. Anyone can read and Pith papers without signing in.