activity
20202026
most citedAtomic fluctuations lifting the energy degeneracy in Si/SiGe quantum dots

78 citations · 311 across the 17 of their papers we have counts for

collaborators

18 papers

cond-mat.mes-hall2026

Spectroscopy With Intelligent Feature Tracking for automated characterization of excited-state structure in semiconductor quantum dot devices

A. R. Huffman, Daniel Schug, Merritt Losert +6

The characterization of excited-state structure in semiconductor quantum dot (QD) devices is an important component of tuning them for spin-qubit operation. We present Spectroscopy…

cond-mat.mes-hall2026

Using a spin-triplet encoding to enhance shuttling fidelities in Si/SiGe quantum wells

Merritt P. R. Losert, S. N. Coppersmith, Mark Friesen

Spatial variations of the valley splitting in a quantum well present a key challenge for conveyor-mode shuttling of electron spins in Si/SiGe, giving rise to Landau-Zener-like exci…

cond-mat.mes-hall2025

Automated electrostatic characterization of quantum dot devices in single- and bilayer heterostructures

Merritt P. R. Losert, Dario Denora, Barnaby van Straaten +6

As quantum dot (QD)-based spin qubits advance toward larger, more complex device architectures, rapid, automated device characterization and data analysis tools become critical. Th…

cond-mat.mes-hall2025★ 1 cited

The effects of alloy disorder on strongly-driven flopping mode qubits in Si/SiGe

Merritt P. R. Losert, Utkan Güngördü, S. N. Coppersmith +2

In Si quantum dot systems, large magnetic field gradients are needed to implement spin rotations via electric dipole spin resonance (EDSR). By increasing the effective electron dip…

cond-mat.mes-hall2025

Statistical characterization of valley coupling in Si/SiGe quantum dots via -factor measurements near a valley vortex

Benjamin D. Woods, Merritt P. Losert, Nasir R. Elston +5

The presence of low-energy valley excitations in Si/SiGe heterostructures often causes spin qubits to fail. It is therefore important to develop robust protocols for characterizing…

cond-mat.mes-hall2025

Engineering Ge profiles in Si/SiGe heterostructures for increased valley splitting

Lucas E. A. Stehouwer, Merrit P. Losert, Maia Rigot +6

Electron spin qubits in Si/SiGe quantum wells are limited by the small and variable energy separation of the conduction band valleys. While sharp quantum well interfaces are pursue…

cond-mat.mes-hall2025★ 5 cited

Valley Splitting Correlations Across a Silicon Quantum Well Containing Germanium

Jonathan C. Marcks, Emily Eagen, Emma C. Brann +12

Quantum dots in SiGe/Si/SiGe heterostructures host coherent electron spin qubits, which are promising for future quantum computers. The silicon quantum well hosts near-degenerate e…

cond-mat.mes-hall2024

g-factor theory of Si/SiGe quantum dots: spin-valley and giant renormalization effects

Benjamin D. Woods, Merritt P. Losert, Robert Joynt +1

Understanding the -factor physics of Si/SiGe quantum dots is crucial for realizing high-quality spin qubits. While previous work has explained some aspects of -factor physics…

quant-ph2024★ 1 cited

Omnidirectional shuttling to avoid valley excitations in Si/SiGe quantum wells

Róbert Németh, Vatsal K. Bandaru, Pedro Alves +7

Conveyor-mode shuttling is a key approach for implementing intermediate-range coupling between electron-spin qubits in quantum dots. Initial implementations are encouraging; howeve…

cond-mat.mes-hall2024★ 3 cited

Suppressing Si Valley Excitation and Valley-Induced Spin Dephasing for Long-Distance Shuttling

Yasuo Oda, Merritt P. Losert, Jason P. Kestner

We present a scalable protocol for suppressing errors during electron spin shuttling in silicon quantum dots. The approach maps the valley Hamiltonian to a Landau-Zener problem to…

cond-mat.mes-hall2024★ 13 cited

Atomistic compositional details and their importance for spin qubits in isotope-purified silicon-germanium quantum wells

Jan Klos, Jan Tröger, Jens Keutgen +10

Understanding crystal characteristics down to the atomistic level increasingly emerges as a crucial insight for creating solid state platforms for qubits with reproducible and homo…

cond-mat.mes-hall2024★ 23 cited

Strategies for enhancing spin-shuttling fidelities in Si/SiGe quantum wells with random-alloy disorder

Merritt P. Losert, Max Oberländer, Julian D. Teske +5

Coherent coupling between distant qubits is needed for any scalable quantum computing scheme. In quantum dot systems, one proposal for long-distance coupling is to coherently trans…

cond-mat.mes-hall2023★ 3 cited

Reducing strain fluctuations in quantum dot devices by gate-layer stacking

Collin C. D. Frink, Talise Oh, E. S. Joseph +5

Nanofabricated metal gate electrodes are commonly used to confine and control electrons in electrostatically defined quantum dots. However, these same gates impart strain-induced p…

cond-mat.mes-hall2023★ 62 cited

Practical Strategies for Enhancing the Valley Splitting in Si/SiGe Quantum Wells

Merritt P. Losert, M. A. Eriksson, Robert Joynt +4

Silicon/silicon-germanium heterostructures have many important advantages for hosting spin qubits. However, controlling the valley splitting (the energy splitting between the two l…

quant-ph2021★ 70 cited

SiGe quantum wells with oscillating Ge concentrations for quantum dot qubits

Thomas McJunkin, Benjamin Harpt, Yi Feng +10

Large-scale arrays of quantum-dot spin qubits in Si/SiGe quantum wells require large or tunable energy splittings of the valley states associated with degenerate conduction band mi…

cond-mat.mes-hall2021★ 78 cited

Atomic fluctuations lifting the energy degeneracy in Si/SiGe quantum dots

Brian Paquelet Wuetz, Merritt P. Losert, Sebastian Koelling +16

Electron spins in Si/SiGe quantum wells suffer from nearly degenerate conduction band valleys, which compete with the spin degree of freedom in the formation of qubits. Despite att…

cond-mat.mes-hall2021★ 37 cited

How valley-orbit states in silicon quantum dots probe quantum well interfaces

J. P. Dodson, H. Ekmel Ercan, J. Corrigan +7

The energies of valley-orbit states in silicon quantum dots are determined by an as yet poorly understood interplay between interface roughness, orbital confinement, and electron i…

cond-mat.mes-hall2020★ 15 cited

Effect of quantum Hall edge strips on valley splitting in silicon quantum wells

Brian Paquelet Wuetz, Merritt P. Losert, Alberto Tosato +10

We determine the energy splitting of the conduction-band valleys in two-dimensional electrons confined to low-disorder Si quantum wells. We probe the valley splitting dependence on…