12 research outputs found
Pauli Blockade in a Few-Hole PMOS Double Quantum Dot limited by Spin-Orbit Interaction
We report on hole compact double quantum dots fabricated using conventional
CMOS technology. We provide evidence of Pauli spin blockade in the few hole
regime which is relevant to spin qubit implementations.
A current dip is observed around zero magnetic field, in agreement with the
expected behavior for the case of strong spin-orbit. We deduce an intradot spin
relaxation rate 120\,kHz for the first holes, an important step
towards a robust hole spin-orbit qubit
All-electrical manipulation of silicon spin qubits with tunable spin-valley mixing
International audienc
Electrical manipulation of semiconductor spin qubits within the g -matrix formalism
International audienc
Electrical Spin Driving by g -Matrix Modulation in Spin-Orbit Qubits
International audienceIn a semiconductor spin qubit with sizable spin-orbit coupling, coherent spin rotations can be driven by a resonant gate-voltage modulation. Recently, we have exploited this opportunity in the experimental demonstration of a hole spin qubit in a silicon device. Here we investigate the underlying physical mechanisms by measuring the full angular dependence of the Rabi frequency, as well as the gate-voltage dependence and anisotropy of the hole g factor. We show that a g-matrix formalism can simultaneously capture and discriminate the contributions of two mechanisms so far independently discussed in the literature: one associated with the modulation of the g factor, and measurable by Zeeman energy spectroscopy, the other not. Our approach has a general validity and can be applied to the analysis of other types of spin-orbit qubits
All-Electrical Control of a Hybrid Electron Spin/Valley Quantum Bit in SOI CMOS Technology
International audienc
Single-Shot Fabrication of Semiconducting–Superconducting Nanowire Devices
Semiconducting–superconducting hybrids are vital components for the realization of high-performance nanoscale devices. In particular, semiconducting–superconducting nanowires attract widespread interest owing to the possible presence of non-abelian Majorana zero modes, which are quasiparticles that hold promise for topological quantum computing. However, systematic search for Majoranas signatures is challenging because it requires reproducible hybrid devices and reliable fabrication methods. This work introduces a fabrication concept based on shadow walls that enables the in situ, selective, and consecutive depositions of superconductors and normal metals to form normal-superconducting junctions. Crucially, this method allows to realize devices in a single shot, eliminating fabrication steps after the synthesis of the fragile semiconductor/superconductor interface. At the atomic level, all investigated devices reveal a sharp and defect-free semiconducting–superconducting interface and, correspondingly, a hard induced superconducting gap resilient up to 2 T is measured electrically. While the cleanliness of the technique enables systematic studies of topological superconductivity in nanowires, it also allows for the synthesis of advanced nano-devices based on a wide range of material combinations and geometries while maintaining an exceptionally high interface quality.QCD/Veldhorst LabQRD/Kouwenhoven LabBUS/Quantum DelftQN/Kouwenhoven La
All-Electrical Control of a Hybrid Electron Spin/Valley Quantum Bit in SOI CMOS Technology
International audienc