Print Email Facebook Twitter Nanoscale mapping of the 3D strain tensor in a Germanium Quantum Well hosting a functional Spin Qubit Device Title Nanoscale mapping of the 3D strain tensor in a Germanium Quantum Well hosting a functional Spin Qubit Device Author Corley-Wiciak, C. Richter, C. Zoellner, M.H. Zaitsev, I. Manganelli, C.L. Zatterin, E. Schülli, T.U. Corley-Wiciak, A.A. Katzer, J. Reichmann, F. Klesse, W.M. Hendrickx, N.W. Sammak, A. Veldhorst, M. Scappucci, G. Virgilio, M. Capellini, G. Publication year 2023 Abstract A strained Ge quantum well, grown on a SiGe/Si virtual substrate and hosting two electrostatically defined hole spin qubits, is nondestructively investigated by synchrotron-based scanning X-ray diffraction microscopy to determine all its Bravais lattice parameters. This allows rendering the three-dimensional spatial dependence of the six strain tensor components with a lateral resolution of approximately 50 nm. Two different spatial scales governing the strain field fluctuations in proximity of the qubits are observed at 1 μm, respectively. The short-ranged fluctuations have a typical bandwidth of 2 × 10–4 and can be quantitatively linked to the compressive stressing action of the metal electrodes defining the qubits. By finite element mechanical simulations, it is estimated that this strain fluctuation is increased up to 6 × 10–4 at cryogenic temperature. The longer-ranged fluctuations are of the 10–3 order and are associated with misfit dislocations in the plastically relaxed virtual substrate. From this, energy variations of the light and heavy-hole energy maxima of the order of several 100 μeV and 1 meV are calculated for electrodes and dislocations, respectively. These insights over material-related inhomogeneities may feed into further modeling for optimization and design of large- scale quantum processors manufactured using the mainstream Si-based microelectronics technology. Subject Lattice strain synchrotronX-ray diffractionQuantum computingSilicon germaniumThermomechanical FEM simulation To reference this document use: http://resolver.tudelft.nl/uuid:2c79e2e7-0a70-4e6c-bc6d-2783a28cf40c DOI https://doi.org/10.1021/acsami.2c17395 TNO identifier 981527 Publisher Amserican Chemical Society ACS Source ACS Applied Materials and Interfaces, 15 (15), 3119-3130 Document type article Files To receive the publication files, please send an e-mail request to TNO Library.