PRIN 2004-2005

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• PRIN 2004-2005
• LECCE PISA TORINO
• MODELS AND NOISE MEASUREMENTS IN NANOSTRUCTURES
• PROJECT STRUCTURE OVERVIEW

Web site www.cmtg.it
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• PROJECT MODELS AND NOISE MEASUREMENTS IN
  
• NANOSTRUCTURES
• Total budget 220.900 (MIUR funding 150.000
  )
• Start date 1st January 2004
• Duration 24 months
• First half year meeting, Lecce, June 18th, 2004
• Coordinator contact details
• DII - University of Lecce Prof. Lino Reggiani
• Administrative in charge Miss Gabriella Panareo

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• Lecce team
• - REGGIANI Lino Prof. Ordinario FIS/03
• - PENNETTA Cecilia Prof. Associato FIS/03
• - ALFINITO Eleonora Ricercatore FIS03
• - ROSINI Marcello Assegnista
• - LEUZZI Maria Tec. Laureato El. Dati
• - COLA Adriano CNR Ricercatore senior
• - MONTAGNA Giovanni CNR Tecnico
• - STARIKOV Jevjenij Semiconductor Physics
  Institute Vilnius Lithuania senior scientist
• - SHIKTOROV Pavel Semiconductor Physics Institute
  Vilnius Lithuania senior scientist
• - REKLAITIS Antanas Semiconductor Physics
  Institute Vilnius Lithuania leading scientist

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• Pisa Team
• - MACUCCI Massimo Prof. Ordinario ING-INF/01
• - BASSO Giovanni Ricercatore ING-INF/01
• - PENNELLI Giovanni Ricercatore ING-INF/01

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• Torino team
• - MAZZETTI Piero Prof. Ordinario FIS/03
• - CARBONE Anna Filomena Ricercatore
  Universitario FIS/03

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• Project Management
• Deliverable 1st year
• Deliverable 2nd year
• Evaluation tasks

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• Lecce first year deliverables
• Milestone 3.1.1
• Theoretical analysis of shot noise in single and
  a double barrier resonant diodes.
• Determination of the spectral density of current
  fluctuations for different geometries and
• different values of the temperature as a function
  of the applied electrical potential.
• Milestone 3.1.2
• Analysis of the Fano factor for the determination
  of the effects due to the electrostatic
• nteraction and the Pauli principle.
• Milestone 3.1.3
• Investigation of the electronic noise in the
  presence of periodic fields of high intensity in
• homostructures and Schottky diodes.
• Milestone 3.1.4
• Development of a stochastic model based on
  percolative techniques for the study of
• excess noise in ultrathin films with intrisic
  defects on an atomic scale length.

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• Pisa first year deliverables
• Milestone 1.1.1
• Development of a code for the simulation of
  transport and shot noise in
• mesoscopic structures, in the presence of
  randomly distributed dopants, with the
• inclusion of realistic confinement potentials.
• Milestone 1.1.2
• Development of an ultra low noise measurement
  system operating at cryogenic
• temperature, using correlation techniques and the
  substitution impedance
• method. The system will be optimized from the
  point of view of its immunity to
• vibrations and interferences of external origin,
  assessing also the thermal stability
• that can be achieved keeping the sample a few
  millimeters over the surface of the
• cryogenic liquid.
• Milestone 1.1.3
• Shot noise measurements on double-barrier
  resonant-tunneling devices, with specific
• emphasis on the low-current operating condition,
  that can be investigated for the first time
• with the new measurement system.

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• Torino first year deliverable
• Milestone 2.1.1
• Development of a suitable statistical model
  accounting for the correlation between
• consecutive electrons in order to determine the
  current noise power spectrum in the
• general case of negative feedback of the electron
  transit through the device.
• Optimization of the noise measurement set-up in
  order to perform measurements of
• optical gain, noise gain and detectivity in
  extreme operative conditions of the devices. In
• particular noise measurements will be performed
  at liquid helium temperature and in
• presence of infrared radiation. The devices are
  supplied by Dr. H.C. Liu (NRC, Canada).
• Milestone 2.1.2
• Measurements of noise in Josephson junctions and
  thin superconducting flms,
• characterized by a very low noise, whose power
  spectral density is of the order of 10(-
• 20) V2/Hz. The junctions can be irradiated by
  means of an optical fiber entering the
• cryostat. This allows to detect the effects of
  the electromagnetic radiation on the I-V
• characteristic and on the noise of the junction.
  Development of a theoretical model able
• to explain the results.

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Lecce second year deliverables Milestone
3.2.1 Comparison of the obtained results for the
shot-noise through Monte Carlo techniques with
those obtained by the partners of the project and
search for unifying microscopic
interpretations. Milestone 3.2.2 Investigation of
the nongaussianity associated with excess noise
of Lorenzian and 1/f type in a biased resistor
network. Milestone 3.2.3 Investigation of the
noise in homojunctions and Schottky diodes
underconditions of periodic fields with high
amplitude and frequency (TeraHertz
region). Milestone 3.2.4 Comparative analysis of
the theoretical approaches developed by this
unity with those developed by partners and/or
exixting in the literature. Comparison of the
theory with the experimental results available
from the literature and/or obtained within the
project.
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• Pisa second year deliverables
• Milestone 1.2.1
• Development of simulation codes for the analysis
  of transport and noise in
• nanostructures, in the presence of a magnetic
  field orthogonal to the fevice plane.
• Optimization of such codes with the application
  of the gauge that is most
• appropriate for the representation of the vector
  potential, on a case by case basis.
• Milestone 1.2.2
• Development of a correlation measurement system
  for the dilution refrigerator that
• is currently being acquired by the group.
• Milestone 1.2.3
• Transport and shot noise measurements on multiple
  chaotic cavities and
• on extended quantum wires characterized by
  partially or completely
• diffusive transport.

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• Torino second year deliverables
• Milestone 2.2.1
• Calculation of the noise power spectrum in multi
  quantum well device on the basis
• of the models.developed in the first year.
  Experimental evaluation of current noise
• as a function of several operating parameters of
  the devices (applied voltage,
• Optical power, photon energy) will be performed.
  Such measurements will be
• exploited to obtain the main figures of merit of
  the devices and to validate the
• above described model.
• Milestone 2.2.2
• Noise measurements on Josephson junctions and
  high Tc superconducting films,
• down to a temperature of 30 millikelvin, using a
  cryostat recently developed in our
• laboratory. The experimental results will be
  compared with the theoretical ones
• expected from the noise generation model
  developed in the first year of activity.

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• EVALUATION TASKS
• At the end of the phase one (12 months) we will
  organize a worksop with the same title of the
  project where each unity will present a
  scientific seminar on the activity carried out.
  The workshop will be publicized at an european
  level to provide an interantional audience on the
  subject.
• The scientific responsible of each unity will
  jointly prepare a conclusive report within the
  time span of the project itself by collecting the
  publications resulted from the project, taking
  into account the impact factor of the journals,
  of the attendance at international and national
  conferences on the subject with oral and poster
  contributions, of the patents which might be
  obtained within the experimental tasks
• .This report will contain a global evaluation of
  the scientific results achieved within the
  project and will be made available on the WEB
  site of the participating Universities.

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• Scheduled Conferences 2005
• Fluctuation and Noise - FaN (may, Texas
  University, USA)
• Unsolved Problems of Noise - UPoN (june,
  Gallipoli Lecce, Italy)
• International Conference on Noise and Flutuations
  ICNF (september, Salamanca, Spain)

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• Patner milestone time due
  status
• Lecce 1 1st year
  pending
• Lecce 2 1st year
  pending
• Lecce 3 1st year
  pending
• Lecce 4 1st year
  pending
• Pisa 1 1st year
  pending
• Pisa 2 1st year
  pending
• Pisa 3 1st year
  pending
• Torino 1 1st year
  pending
• Torino 2 1st year
  pending

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• Patner milestone time due
  status
• Lecce 1 2nd year
  pending
• Lecce 2 2nd year
  pending
• Lecce 3 2nd year
  pending
• Lecce 4 2nd year
  pending
• Pisa 1 2nd year
  pending
• Pisa 2 2nd year
  pending
• Pisa 3 2nd year
  pending
• Torino 1 2nd year
  pending
• Torino 2 2nd year
  pending

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• Workplan revisions and triggering of
• contingency plans