- document
-
Lodari, M. (author), Kong, O. (author), Rendell, M. (author), Tosato, A. (author), Sammak, A. (author), Veldhorst, M. (author), Hamilton, A.R. (author), Scappucci, G. (author)We demonstrate that a lightly-strained germanium channel ("// = −0.41%) in an undoped Ge/Si0.1Ge0.9 heterostructure field effect transistor supports a 2D hole gas with mobility in excess of 1 × 106 cm2/Vs and percolation density less than 5 × 1010 cm−2. This low disorder 2D hole system shows tunable fractional quantum Hall effect at low density...article 2022
- document
-
Harvey-Collard, P. (author), Dijkema, J. (author), Zheng, G. (author), Sammak, A. (author), Scappucci, G. (author), Vandersypen, L.M.K. (author)We report the coherent coupling of two electron spins at a distance via virtual microwave photons. Each spin is trapped in a silicon double quantum dot at either end of a superconducting resonator, achieving spin-photon couplings up to around gs/2π = 40 MHz. As the two spins are brought into resonance with each other, but detuned from the...article 2022
- document
-
Degli Esposti, D. (author), Paquelet Wuetz, B. (author), Fezzi, V. (author), Lodari, M. (author), Sammak, A. (author), Scappucci, G. (author)We grow 28Si/SiGe heterostructures by reduced-pressure chemical vapor deposition and terminate the stack without an epitaxial Si cap but with an amorphous Si-rich layer obtained by exposing the SiGe barrier to dichlorosilane at 500 °C. As a result, 28Si/SiGe heterostructure field-effect transistors feature a sharp semiconductor/dielectric...article 2022
- document
-
Tosato, A. (author), Ferrari, B. (author), Sammak, A. (author), Hamilton, A.R. (author), Veldhorst, M. (author), Virgilio, M. (author), Scappucci, G. (author)A hole bilayer in a strained germanium double quantum well is designed, fabricated, and studied. Magnetotransport characterization of double quantum well field-effect transistors as a function of gate voltage reveals the population of two hole channels with a high combined mobility of 3.34 × 105 cm2 V−1 s−1 and a low percolation density of 2.38 ...article 2022
- document
-
Prabowo, B. (author), Zheng, G. (author), Mehrpoo, M. (author), Patra, B. (author), Harvey-Collard, P. (author), Dijkema, J. (author), Sammak, A. (author), Scappucci, G. (author), Charbon, E. (author), Sebastiano, F. (author), Vandersypen, L.M.K. (author), Babaie, M. (author)Quantum computers (QC) promise to solve certain computational problems exponentially faster than a classical computer due to the superposition and entanglement properties of quantum bits (qubits). Among several qubit technologies, spin qubits are a promising candidate for large-scale QC, since (1) they have a small footprint allowing them to be...conference paper 2021
- document
-
Rossi, A. (author), Hendrickx, N.W. (author), Sammak, A. (author), Veldhorst, M. (author), Scappucci, G. (author), Kataoka, M. (author)Single-charge pumps are the main candidates for quantum-based standards of the unit ampere because they can generate accurate and quantized electric currents. In order to approach the metrological requirements in terms of both accuracy and speed of operation, in the past decade there has been a focus on semiconductor-based devices. The use of a...article 2021
- document
-
Hendrickx, N.W. (author), Lawrie, W.I.L. (author), Russ, M. (author), van Riggelen, F. (author), de Snoo, S.L. (author), Schouten, R.N. (author), Sammak, A. (author), Scappucci, G. (author), Veldhorst, M. (author)The prospect of building quantum circuits using advanced semiconductor manufacturing makes quantum dots an attractive platform for quantum information processing. Extensive studies of various materials have led to demonstrations of two-qubit logic in gallium arsenide, silicon and germanium. However, interconnecting larger numbers of qubits in...article 2021
- document
-
van Riggelen, F (author), Hendrickx, N.W. (author), Lawrie, W.I.L. (author), Russ, M. (author), Sammak, A. (author), Scappucci, G. (author), Veldhorst, M. (author)Quantum dots fabricated using techniques and materials that are compatible with semiconductor manufacturing are promising for quantum information processing. While great progress has been made toward high-fidelity control of quantum dots positioned in a linear arrangement, scalability along two dimensions is a key step toward practical quantum...conference paper 2021
- document
-
Aggarwal, K. (author), Hofmann, A. (author), Jirovec, D. (author), Prieto, I. (author), Sammak, A. (author), Botifoll, M. (author), Martí-Sánchez, S. (author), Veldhorst, M. (author), Arbiol, J. (author), Scappucci, G. (author), Danon, J. (author), Katsaros, G. (author)Hole gases in planar germanium can have high mobilities in combination with strong spin-orbit interaction and electrically tunable g factors, and are therefore emerging as a promising platform for creating hybrid superconductor-semiconductor devices. A key challenge towards hybrid Ge-based quantum technologies is the design of high-quality...article 2021
- document
-
Lawrie, W.I.L. (author), Eenink, H.G.J. (author), Hendrickx, N.W. (author), Boter, J.M. (author), Petit, L. (author), Amitonov, S.V. (author), Lodari, M. (author), paquelet Wuetz, B. (author), Volk, C. (author), Philips, S.G.J. (author), Droulers, G. (author), Kalhor, N. (author), van Riggelen, F. (author), Brousse, D. (author), Sammak, A. (author), Vandersypen, L.M.K. (author), Scappucci, G. (author), Veldhorst, M. (author)Electrons and holes confined in quantum dots define excellent building blocks for quantum emergence, simulation, and computation. Silicon and germanium are compatible with standard semiconductor manufacturing and contain stable isotopes with zero nuclear spin, thereby serving as excellent hosts for spins with long quantum coherence. Here, we...article 2020
- document
-
Last, T. (author), Samkharadze, N. (author), Eendebak, P.T. (author), Versluis, R. (author), Xue, X. (author), Sammak, A. (author), Brousse, D. (author), Loh, K.K.L. (author), Polinder, H. (author), Scappucci, G. (author), Veldhorst, M. (author), Vandersypen, L. (author), Maturová, K. (author), Veltin, J. (author), Alberts, G.J.N. (author)The mission of QuTech is to bring quantum technology to industry and society by translating fundamental scientific research into applied research. To this end we are developing Quantum Inspire (QI), a full-stack quantum computer prototype for future co-development and collaborative R&D in quantum computing. A prerelease of this prototype system...conference paper 2020
- document
-
Xu, Y. (author), Unseld, F.K. (author), Corna, A. (author), Zwerver, A.M.J. (author), Sammak, A. (author), Brousse, D. (author), Samkharadze, N. (author), Amitonov, S.V. (author), Veldhorst, M. (author), Scappucci, G. (author), Ishihara, R. (author), Vandersypen, L.M.K. (author)Solid-state qubits integrated on semiconductor substrates currently require at least one wire from every qubit to the control electronics, leading to a so-called wiring bottleneck for scaling. Demultiplexing via on-chip circuitry offers an effective strategy to overcome this bottleneck. In the case of gate-defined quantum dot arrays, specific...article 2020
- document
-
Harvey-Collard, P. (author), Zheng, G. (author), Dijkema, J. (author), Samkharadze, N. (author), Sammak, A. (author), Scappucci, G. (author), Vandersypen, L.M.K. (author)Circuit quantum electrodynamics (QED) employs superconducting microwave resonators as quantum buses. In circuit QED with semiconductor quantum-dot-based qubits, increasing the resonator impedance is desirable as it enhances the coupling to the typically small charge dipole moment of these qubits. However, the gate electrodes necessary to form...article 2020
- document
-
Hendrickx, N.W. (author), Franke, D.P. (author), Sammak, A. (author), Scappucci, G. (author), Veldhorst, M. (author)Universal quantum information processing requires the execution of single-qubit and two-qubit logic. Across all qubit realizations1, spin qubits in quantum dots have great promise to become the central building block for quantum computation2. Excellent quantum dot control can be achieved in gallium arsenide3–5, and high-fidelity qubit rotations...article 2020
- document
-
Del Vecchio, P. (author), Lodari, M. (author), Sammak, A. (author), Scappucci, G. (author), Moutanabbir, O. (author)A clear signature of Zeeman split states crossing is observed in a Landau fan diagram of strained germanium two-dimensional hole gas. The underlying mechanisms are discussed based on a perturbative model yielding a closed formula for the critical magnetic fields. These fields depend strongly on the energy difference between the topmost and...article 2020
- document
-
Patra, B. (author), van Dijk, J.P.G. (author), Subramanian, S. (author), Corna, A. (author), Xue, X. (author), Jeon, C. (author), Sheikh, F. (author), Juarez-Hernandez, E. (author), Esparza, B.P. (author), Rampurawala, H. (author), Carlton, B. (author), Samkharadze, N. (author), Ravikumar, S. (author), Nieva, C. (author), Kim, S. (author), Lee, H.J. (author), Sammak, A. (author), Scappucci, G. (author), Veldhorst, M. (author), Vandersypen, L.M.K. (author), Babaie, M. (author), Sebastiano, F. (author), Charbon, E. (author), Pellerano, S. (author)Quantum computers (QC), comprising qubits and a classical controller, can provide exponential speed-up in solving certain problems. Among solid-state qubits, transmons and spin-qubits are the most promising, operating ≪ 1K. A qubit can be implemented in a physical system with two distinct energy levels representing the |0⟩ and |1⟩ states, e.g....conference paper 2020
- document
-
Xue, X. (author), Patra, B. (author), van Dijk, J.P.G. (author), Samkharadze, N. (author), Subramanian, S. (author), Corna, A. (author), Jeon, C. (author), Sheikh, F. (author), Juarez-Hernandez, E. (author), Perez Esparza, B. (author), Rampurawala, H. (author), Varlton, B. (author), Ravikumar, S. (author), Nieva, C. (author), Kim, S. (author), Lee, H.J. (author), Sammak, A. (author), Scappucci, G. (author), Veldhorst, M. (author), Sebastiano, F. (author), Babaie, M. (author), Pellerano, S. (author), Charbon, E. (author), Vandersypen, L.M.K. (author)The most promising quantum algorithms require quantum processors hosting millions of quantum bits when targeting practical applications. A major challenge towards large-scale quantum computation is the interconnect complexity. In current solid-state qubit implementations, a major bottleneck appears between the quantum chip in a dilution...conference paper 2020
- document
- Lodari, M. (author), Hendrickx, N.W. (author), Lawrie, W.I.L. (author), Hsiao, T.K. (author), Vandersypen, L.M.K. (author), Sammak, A. (author), Veldhorst, M. (author), Scappucci, G. (author) conference paper 2020
- document
-
Paquelet Wütz, B. (author), Losert, M.P. (author), Tosato, A. (author), Lodari, M. (author), Bavdaz, P.L. (author), Stehouwer, L. (author), Amin, P. (author), Clarke, J.S. (author), Coppersmith, S.N. (author), Sammak, A. (author), Veldhorst, M. (author), Friesen, M. (author), Scappucci, G. (author)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 both perpendicular magnetic field B and Hall density by performing activation energy measurements in the quantum Hall regime over a large range of filling factors....article 2020
- document
-
van Dijk, J.P.G. (author), Patra, B. (author), Subramanian, S. (author), Xue, X. (author), Samkharadze, N. (author), Corna, A. (author), Jeon, C. (author), Sheikh, F. (author), Juarez-Hernandez, E. (author), Perez Esparza, B. (author), Rampurawala, H. (author), Carlton, B.R. (author), Ravikumar, S. (author), Nieva, C. (author), Kim, S. (author), Lee, H.J. (author), Sammak, A. (author), Scappucci, G. (author), Veldhorst, M. (author), Vandersypen, L.M.K. (author), Charbon, E. (author), Pellerano, S. (author), Babaie, M. (author), Sebastiano, F. (author)Building a large-scale quantum computer requires the co-optimization of both the quantum bits (qubits) and their control electronics. By operating the CMOS control circuits at cryogenic temperatures (cryo-CMOS), and hence in close proximity to the cryogenic solid-state qubits, a compact quantumcomputing system can be achieved, thus promising...article 2020