Coherence Protection for Mobile Spin Qubits in Silicon

Fuente: arXiv
Saved in:
Bibliographic Details
Main Authors: Krzywda, Jan A., Matsumoto, Yuta, De Smet, Maxim, Tryputen, Larysa, de Snoo, Sander L., Amitonov, Sergey V., van Nieuwenburg, Evert, Scappucci, Giordano, Vandersypen, Lieven M. K.
Format: Preprint
Published: 2026
Subjects:
Online Access:
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866914322898223104
author Krzywda, Jan A.
Matsumoto, Yuta
De Smet, Maxim
Tryputen, Larysa
de Snoo, Sander L.
Amitonov, Sergey V.
van Nieuwenburg, Evert
Scappucci, Giordano
Vandersypen, Lieven M. K.
author_facet Krzywda, Jan A.
Matsumoto, Yuta
De Smet, Maxim
Tryputen, Larysa
de Snoo, Sander L.
Amitonov, Sergey V.
van Nieuwenburg, Evert
Scappucci, Giordano
Vandersypen, Lieven M. K.
contents Mobile spin qubit architectures promise flexible connectivity for efficient quantum error correction and relaxed device layout constraints, but their viability rests on preserving spin coherence during transport. While shuttling transforms spatial disorder into time-dependent noise, its net impact on spin coherence remains an open question. Here we demonstrate systematic noise mitigation during spin shuttling in a linear $^{28}$Si/SiGe quantum dot device. First, by passively reducing magnetic field gradients, we minimize charge-noise coupling to the spin and double the spatially averaged dephasing time $T_2^*(x_n)$ from $4.4$ to $8.5\,μ\text{s}$. Next, we exploit motional narrowing by periodically shuttling the qubit, achieving a further enhancement in coherence time up to $T_{2}^{*,sh} = 11.5\,μ\text{s}$. Finally, we incorporate dynamical decoupling techniques while periodically shuttling over distances exceeding $200\,\text{nm}$, reaching $T_\text{2}^{H,sh}= 32\,μ\text{s}$. For the same setup, we demonstrate that dressed-state shuttling provides robust protection against low-frequency noise with a decay time $T_R^{\text{sh}} = 21\,μ\text{s}$, without the overhead of pulsed control and allowing protection during one-way spin transport. By preserving coherence over timescales exceeding typical gate and readout operations, the demonstrated strategies establish mobile spin qubits as a viable solution for scalable silicon quantum processors.
format Preprint
id arxiv_https___arxiv_org_abs_2602_09179
institution arXiv
publishDate 2026
record_format arxiv
spellingShingle Coherence Protection for Mobile Spin Qubits in Silicon
Krzywda, Jan A.
Matsumoto, Yuta
De Smet, Maxim
Tryputen, Larysa
de Snoo, Sander L.
Amitonov, Sergey V.
van Nieuwenburg, Evert
Scappucci, Giordano
Vandersypen, Lieven M. K.
Mesoscale and Nanoscale Physics
Quantum Physics
Mobile spin qubit architectures promise flexible connectivity for efficient quantum error correction and relaxed device layout constraints, but their viability rests on preserving spin coherence during transport. While shuttling transforms spatial disorder into time-dependent noise, its net impact on spin coherence remains an open question. Here we demonstrate systematic noise mitigation during spin shuttling in a linear $^{28}$Si/SiGe quantum dot device. First, by passively reducing magnetic field gradients, we minimize charge-noise coupling to the spin and double the spatially averaged dephasing time $T_2^*(x_n)$ from $4.4$ to $8.5\,μ\text{s}$. Next, we exploit motional narrowing by periodically shuttling the qubit, achieving a further enhancement in coherence time up to $T_{2}^{*,sh} = 11.5\,μ\text{s}$. Finally, we incorporate dynamical decoupling techniques while periodically shuttling over distances exceeding $200\,\text{nm}$, reaching $T_\text{2}^{H,sh}= 32\,μ\text{s}$. For the same setup, we demonstrate that dressed-state shuttling provides robust protection against low-frequency noise with a decay time $T_R^{\text{sh}} = 21\,μ\text{s}$, without the overhead of pulsed control and allowing protection during one-way spin transport. By preserving coherence over timescales exceeding typical gate and readout operations, the demonstrated strategies establish mobile spin qubits as a viable solution for scalable silicon quantum processors.
title Coherence Protection for Mobile Spin Qubits in Silicon
topic Mesoscale and Nanoscale Physics
Quantum Physics
url https://arxiv.org/abs/2602.09179