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allied
academies
August 23-24, 2018 | Paris, France
Laser, Optics and Photonics
International Conference on
Journal of Materials Science and Nanotechnology | Volume: 2
Generation and visualization of few electron states in a quantum conductor
Bisognin Remi, Kumar Manohar, Roussel Benjamin, Cabart Clement, Bocquillon Erwann, Berroir Jean-Marc, Plaais Bernard, Cavanna
Antonella, Gennser Ulf, Jin Young, Chapdelaine Camille, Mohammad-Djafari Ali, Degiovanni Pascal
and
Feve Gwendal
CNRS - Pierre Aigrain Laboratory, France
T
hanks to the recent development in nanoelectronics,
we can now study the quantum properties of electrical
currents at the elementary excitation level. This naturally
leads to the following question: can we experimentally extract
from an electrical current its elementary excitations and fully
characterize their coherence properties? In this work by driving
locally a 1D conductor with a Lorentzian drive, we generate
current pulses carrying one or two elementary excitations.
Using two-particle interferometry, we fully reconstruct the
wavefunction of the excitations propagating in the conductor.
By shaping the width of the current pulses, we can engineer
single electron wavefunctions of controlled energy and time
distributions related by the Heisenberg uncertainty principle.
To implement these electron quantum optics experiments, we
use a model conductor which consists in a 2D electron gas in
the integer quantum Hall effect at very low temperature. In
this regime charges propagate along 1D ballistic edge channels
which are used to characterize elementary excitations in
electronic interferometers. The wavefunction measurement
is based on a general quantum tomography protocol. The
protocol relies on repeated overlap measurements between
the generated current pulses and a set of reference probes in
a Hong Ou-Mandel electronic interferometer. The reduction
of the low frequency shot noise at the interferometer output
is a direct measurement of this overlap. The wavefunction is
extracted in two steps. First, we reconstruct the time-energy
Wigner representation of the electronic current using all
overlaps. Secondly a signal-processing algorithm decomposes
the Wigner distribution in its elementary building blocks: the
single electron wavefunctions. By demonstrating the controlled
generation and the visualization of few electron states in a
quantum conductor, this work opens new perspectives in
quantum nanoelectronics.
Speaker Biography
Bisognin Remi currently a PhD student in the Quantum Electron Optics group of the
Pierre Aigrain Laboratory. He is doing his PhD under the supervision of Gwendal Feve.
His research interest are Quantum Optics, Optical Networks and Quantum Electron.
e:
remi.bisognin@lpa.ens.frNotes: