The
Waterloo
Institute
for
Nanotechnology
(WIN)
has
launched
a
new
seminar
series,
Quantum
Nano
Collision
(QNC)
Seminar
Series,
to
deepen
the
engagement
of
the
Waterloo
researchers
who
work
at
the
interface
of
quantum
and
nanotechnologies.
This
seminar
series
will
also
provide
opportunities
for
senior
graduate
students,
post-doctoral
fellows,
and
research
associates
to
present
their
innovative
work
along
with
the
faculty
members
to
bring
together
the
excitement
around
these
cutting-edge
technologies
that
would
shape
our
future.
The
next
talk
for
the
QNC
Seminar
Series
will
be
delivered
by
Professor
Jonathan
Baugh.
Registration is required. If you have any questions or issues registering, please contact win-office@uwaterloo.ca
Single-electron devices and their applications in quantum information
This talk will focus on quantum nanoelectronic devices, built on the versatile platform of the two-dimensional electron gas (2DEG), and some of their applications. Ultra-high mobility AlGaAs/GaAs heterostructures typically contain dopant layers to provide carriers, however, a 2DEG can be electrostatically induced by a top gate in an undoped structure. Dopant-free devices are more challenging to fabricate, but have superior reproducibility and lower disorder. Moreover, they can be ambipolar: both hole (P type) and electron (N type) gases can be induced [1]. We demonstrate the diode behaviour of a lateral PN junction and characterize the electroluminescence that occurs under a sufficient PN bias voltage. We also demonstrate the first one-parameter single-electron pump (dynamic quantum dot) in undoped GaAs [2], and discuss how it can be used in metrology (defining the Ampere) or be combined with a PN junction to realize a novel on-demand source of single photons. Next, we focus on electron spin qubits in silicon MOS quantum dots, and the prospects for building a large-scale processor. We propose a node/network architecture for implementing surface code quantum error correction. The scheme splits the scalability problem in two parts: inter-node entanglement distribution and intra-node operations [3]. This approach relaxes constraints on wiring densities and allows the co-integration of readout and multiplexing circuits. I will discuss our experimental efforts to simplify the design of Si MOS quantum dots to improve prospects for scalability [4].
References
- Effects of biased and unbiased illuminations on dopant-free GaAs/AlGaAs 2DEGs, A. Shetty et al, J. Baugh, Phys. Rev. B 105, 075302 (2022).
- Non-adiabatic single-electron pump in a dopant-free GaAs/AlGaAs 2DEG. B. Buonacorsi et al, J. Baugh, Applied Physics Letters 119, 114001 (2021).
- Network architecture for a topological quantum computer in silicon, B. Buonacorsi et al, J. Baugh, Quantum Science and Technology 4, 025003 (2019).
- Few-electrode design for silicon MOS quantum dots, E. B. Ramirez, F. Sfigakis, S. Kudva, J. Baugh, Semiconductor Science and Technology 35, 015002 (2019).
Speaker Biography
Jonathan Baugh is a Professor of Chemistry and member of the Institute for Quantum Computing and WIN at the University of Waterloo. His research group investigates the potential of semiconductor nanoelectronics for scalable quantum information processing. Dr. Baugh obtained a PhD in Physics (2001) at the University of North Carolina at Chapel Hill. He did seminal work on nuclear magnetism in quantum dots during postdoctoral studies at the University of Tokyo prior to joining Waterloo as a faculty member in 2007. He has published more than 70 papers across many research areas, including magnetic resonance, quantum control, quantum transport, quantum dots, nanowires, proximity superconductivity, nanomechanics and materials science.