SiQuBus – QuantEra consortium

Project QuantEra Si-QiBus entitled
“Long-range quantum bus for electron spin qubits in silicon” (2018-2021)

This QuantEra project is being carried out by the European Si-QuBus consortium that consists of six partners working tightly together in order to realize a QuBus in silicon. The six principal investigators and groups are:


The Objective

The goal of the project is to demonstrate long-distance transfer of electron spin qubit in a silicon nanostructure. We want to coherently transfer an electron in a superposition of its spin states along a chain of gate-defined quantum dots. Achiecing this objective will allow for significant progress in scaling of quantum-dot based spin qubits in semiconductor architecture.


Main results obtained so far with the involvement of the Warsaw group (for  all the results see the consortium website)

1) Development of theoretical  description of adiabatic electron electron transfer between two quantum dots in presence of 1/f charge noise [1].

2)Theoretical assistance in elucidation of dominant sources of decoherence of a silicon quantum dot based spin qubits controlled by a nearby nanomagnet [2].



[4] V. Langrock, J. A. Krzywda, N. Focke, I. Seidler, L. R. Schreiber, and and Ł. Cywiński
Blueprint of a scalable spin qubit shuttle device for coherent mid-range qubit transfer in disordered Si/SiGe/SiO2

[3] J. A. Krzywda and Ł. Cywiński
Interplay of charge noise and coupling to phonons in adiabatic electron transfer between quantum dots
Phys. Rev. B 104, 075439 (2021)

[2] T. Struck, A. Hollmann, F. Schauer, O. Fedorets, A. Schmidbauer, K. Sawano,
H. Riemann, N. V. Abrosimov, Ł. Cywinski, D. Bougeard, and L. R. Schreiber
Low-frequency spin qubit detuning noise in highly purified 28Si/SiGe
npj Quantum Information 6, 40 (2020)

[1] J. A. Krzywda  and Ł. Cywiński
Adiabatic electron charge transfer between two quantum dots in presence of 1/ f noise
Phys. Rev. B 101, 035303 (2020)