Quantum dot arrays in silicon and germanium

Quantum dot arrays in silicon and germanium

Lawrie, W.I.L.
Eenink, H.G.J.
Hendrickx, N.W.
Boter, J.M.
Petit, L.
Amitonov, S.V.
Lodari, M.
paquelet Wuetz, B.
Volk, C.
Philips, S.G.J.
Droulers, G.
Kalhor, N.
van Riggelen, F.
Brousse, D.
Sammak, A.
Vandersypen, L.M.K.
Scappucci, G.
Veldhorst, M.

2020

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 demonstrate quantum dot arrays in a silicon metal-oxide-semiconductor (SiMOS), strained silicon (Si/SiGe), and strained germanium (Ge/SiGe). We fabricate using a multi-layer technique to achieve tightly confined quantum dots and compare integration processes. While SiMOS can benefit from a larger temperature budget and Ge/SiGe can make an Ohmic contact to metals, the overlapping gate structure to define the quantum dots can be based on a nearly identical integration. We realize charge sensing in each platform, for the first time in Ge/SiGe, and demonstrate fully functional linear and two-dimensional arrays where all quantum dots can be depleted to the last charge state. In Si/SiGe, we tune a quintuple quantum dot using the N + 1 method to simultaneously reach the few electron regime for each quantum dot. We compare capacitive crosstalk and find it to be the smallest in SiMOS, relevant for the tuning of quantum dot arrays. We put these results into perspective for quantum technology and identify industrial qubits, hybrid technology, automated tuning, and two-dimensional qubit arrays as four key trajectories that, when combined, enable fault-tolerant quantum computation.

Budget control
Carbon Quantum Dots
Graphene quantum dots
Metals
MOS devices
Nanocrystals
Ohmic contacts
Oxide semiconductors
Quantum optics
Qubits
Semiconductor device manufacture
Silicon compounds
Strained silicon
Tuning
Capacitive crosstalk
Electrons and holes
Fault-tolerant quantum computation
Integration process
Metal oxide semiconductor
Quantum technologies
Semiconductor manufacturing
Two-dimensional arrays
Semiconductor quantum dots

http://resolver.tudelft.nl/uuid:0a8d6ff0-8254-42dc-854e-8fb08fa6e603

https://doi.org/10.1063/5.0002013

875128

American Institute of Physics AIP

0003-6951

Applied Physics Letters, 116 (8)

80501

article