18 research outputs found
Pauli spin blockade in CMOS double quantum dot devices
Silicon quantum dots are attractive candidates for the development of
scalable, spin-based qubits. Pauli spin blockade in double quantum dots
provides an efficient, temperature independent mechanism for qubit readout.
Here we report on transport experiments in double gate nanowire transistors
issued from a CMOS process on 300 mm silicon-on-insulator wafers. At low
temperature the devices behave as two few-electron quantum dots in series. We
observe signatures of Pauli spin blockade with a singlet-triplet splitting
ranging from 0.3 to 1.3 meV. Magneto-transport measurements show that
transitions which conserve spin are shown to be magnetic-field independent up
to B = 6 T.Comment: 5 pages , 4 figure
A CMOS silicon spin qubit
Silicon, the main constituent of microprocessor chips, is emerging as a
promising material for the realization of future quantum processors. Leveraging
its well-established complementary metal-oxide-semiconductor (CMOS) technology
would be a clear asset to the development of scalable quantum computing
architectures and to their co-integration with classical control hardware. Here
we report a silicon quantum bit (qubit) device made with an industry-standard
fabrication process. The device consists of a two-gate, p-type transistor with
an undoped channel. At low temperature, the first gate defines a quantum dot
(QD) encoding a hole spin qubit, the second one a QD used for the qubit
readout. All electrical, two-axis control of the spin qubit is achieved by
applying a phase-tunable microwave modulation to the first gate. Our result
opens a viable path to qubit up-scaling through a readily exploitable CMOS
platform.Comment: 12 pages, 4 figure
Excited state spectroscopy and spin splitting in atomically thin quantum dots
Semiconducting transition metal dichalcogenides (TMDCs) are very promising
materials for quantum dots and spin-qubit implementation. Reliable operation of
spin qubits requires the knowledge of Land\'e g-factor, which can be measured
by exploiting the discrete energy spectrum on a quantum dot. However, the
quantum dots realized in TMDCs has yet to reach the required quality for
reliable measurement of g-factor. Quantum dot sizes reported in TMDCs so far
are not small enough to observe discrete energy levels on them. Here, we report
on electron transport through discrete energy levels of quantum dot in a single
layer MoS2. The quantum dot energy levels are separated by few (5-6) meV such
that the ground state and the excited state transitions are clearly visible.
This well resolved energy separation allows us to accurately measure the ground
state g-factor of ~5 in MoS2 quantum dots. We observe a spin filling sequence
in our quantum dot under perpendicular magnetic field. Such a system offers an
excellent testbed to measure the key parameters for evaluation and
implementation of spin-valley qubits in TMDCs, thus accelerating the
development of quantum systems in two dimensional semiconducting TMDCs.Comment: 17 pages, 10 figure
Mass Production of Silicon MOS-SETs: Can We Live with Nano-Devices’ Variability?
AbstractIt is very important to study variability of nanodevices because the inability to produce large amounts of identical nanostructures is eventually a bottleneck for any application. In fact variability is already a major concern for CMOS circuits. In this work we report on the variability of dozens of silicon single-electron transistors (SETs). At room temperature their variability is compared with the variability of the most advanced CMOS FET i.e. the ultra thin Silicon-on-Insulator Multiple gate FET (UT SOI MuGFET). We found that dopants diffused from Source –Drain into the edge of the undoped channel are the main source of variability. This emphasizes the role of extrinsic factors like the contact junctions for variability of any nanodevice
Single layer MoS2 nanoribbon field effect transistor
10.1063/1.5079860APPLIED PHYSICS LETTERS114
Si CMOS platform for quantum information processing
International audienc