Isaac Silvera

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Current Hot Areas of Research in Physics
Isaac Silvera Lyman Laboratory of
Physics Harvard University
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Mature Physics and Hot Physics
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• Cold atom physics (Bose-Einstein condensation
  and degenerate Fermi gases),
• Condensed matter
• supersolids, correlated electrons,
  nanophysics metallic hydrogen,
  etc,
• Biophysics
• Soft condensed matter,
• Hydrogen storagethe energy problem
• Astrophysics dark matter and dark energy
• Quantum computing,
• Neutrino physics,
• String theory
• Particle physics, the Large Hadron Collider, the
  Higgs particle, Supersymmetric particles

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• Cold atom physics (Bose-Einstein condensation
  and degenerate Fermi gases),
• Condensed matter
• supersolids, correlated electrons,
  nanophysics metallic hydrogen,
  etc,
• Biophysics
• Soft condensed matter,
• Hydrogen storagethe energy problem
• Astrophysics dark matter and dark energy
• Quantum computing,
• Neutrino physics,
• String theory
• Particle physics, the Large Hadron Collider, the
  Higgs particle, Supersymmetric particles

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Bose-Einstein Condensation (BEC)
In 1924 Einstein predicted that a gas of bosons
(identical integral spin particles) would have a
phase transition below a finite critical
temperature the ground energy state or zero
momentum state would be macroscopically occupied
by particles. It was believed that superfluid
helium was a demonstration of BEC but this was
controversial and difficult to demonstrate
experimentally.
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In 1979 the first confined gas of bosons,
spin-polarized atomic hydrogen was stabilized,
but the conditions for BEC were difficult to
achieve. In the 1980s atomic physicists learned
how to cool alkali atoms (sodium, rubidium,etc.)
to microkelvin temperatures Alkali gases
(metastable) were confined in magnetic traps that
isolated them from walls and prevented
condensation. They were cooled by evaporative
cooling--removal of hot atoms, allowing the
remaining atoms to thermalize to a lower
temperature-- and finally BEC at nanokelvin
Temperature!
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Vertical the probability the an energy state is
occupied Horizontal energy increasing radially.
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Cornell and Weiman (U. of Colorado) and Ketterle
(MIT) received Nobel Prize Almost every Physics
department has a cold atom group. Atomic
physicists have become condensed matter
physicists. 5-10 new publications/week BEC atoms
are superfluids superfluid vortices, atom laser,
cold fermions superfluid fermions, etc.
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• Cold atom physics (Bose-Einstein condensation
  and degenerate Fermi gases),
• Condensed matter
• supersolids, correlated electrons,
  nanophysics metallic hydrogen,
  etc,
• Biophysics
• Soft condensed matter,
• Hydrogen storagethe energy problem
• Astrophysics dark matter and dark energy
• Quantum computing,
• Neutrino physics,
• String theory
• Particle physics, the Large Hadron Collider, the
  Higgs particle, Supersymmetric particles

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High Q torsional oscillator for detecting non
classical moment of inertia, or superfluidity, I.
Be-Cu Torsion Rod
Torsion Bob containing helium
Drive
Detection
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Supersolid Response. Solid helium exhibits
superflow.
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Nanophysics and Lower dimensional physics.
In the late 1980s physicists at IBM Watson
Research laboratories found that small high
purity samples did not obey Ohms Law ViR
Electron quantum mechanical amplitude could move
on the upper or lower path and get quantum
interference.--if there was no inelastic
scattering and the electrons maintained there
phase over the path length.
i
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• This led to rapid development of the study of
  materials on a microscopic-nanoscopic-scale and
  the study of materials in lower dimensions. What
  developed
• Integral and fractional quantum Hall
  effect-2-dimensional electron gases.
• Single electron transistor
• Quantum dots Coulomb blockade artificial atoms
• Bucky balls
• Carbon nanotubes
• Etc.

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Quantum dot and circuit
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A carbon nanotube suspended between two
conductors.
Raman scattering spectrum Of vibrational modes
in the Single walled carbon NT
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Fracture of nanoscopic 2d organosilicate glass
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• Cold atom physics (Bose-Einstein condensation
  and degenerate Fermi gases),
• Condensed matter
• supersolids, correlated electrons,
  nanophysics metallic hydrogen,
  etc,
• Biophysics
• Soft condensed matter,
• Hydrogen storagethe energy problem
• Astrophysics dark matter and dark energy
• Quantum computing,
• Neutrino physics,
• String theory
• Particle physics, the Large Hadron Collider, the
  Higgs particle, Supersymmetric particles

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• IMPORTANT DEVELOPMENTS
• Predicted Metal Insulator Transition in Solid
  Hydrogen Wigner-Huntington, 1935
• Predicted High Temperature Superconductivity in
  Metallic Hydrogen Ashcroft, 1968
• Metastability of metallic hydrogen, liquid at
  T0 K Russia
  (Kolos, Kagan), 1972
• New Megabar Phases in the High Pressure Solid
  Hydrogens 1980-2005
  
  BSP Amsterdam 1981,
  Harvard 1990
• A-Phase (III) Geophys. Lab, Harvard, 1989-1990,
  2005

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Superconducting electrons Superconducting
protons Superfluidity of both together
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The heart of a diamond anvil cell (DAC).
Pressures higher than 3 million bars can be
achieved on samples inside the gasket hole.
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• Cold atom physics (Bose-Einstein condensation
  and degenerate Fermi gases),
• Condensed matter
• supersolids, correlated electrons,
  nanophysics metallic hydrogen,
  etc,
• Biophysics
• Soft condensed matter,
• Hydrogen storagethe energy problem
• Astrophysics dark matter and dark energy
• Quantum computing,
• Neutrino physics,
• String theory
• Particle physics, the Large Hadron Collider, the
  Higgs particle, Supersymmetric particles

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A method for rapid sequencing of DNA
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Sequencing of DNA a different conductance
for Each base (C,G, A, T). In principle the DNA
code Could be read in one millisecond.
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• Cold atom physics (Bose-Einstein condensation
  and degenerate Fermi gases),
• Condensed matter
• supersolids, correlated electrons,
  nanophysics metallic hydrogen, etc,
• Biophysics
• Soft condensed matter,
• Hydrogen storagethe energy problem
• Astrophysics dark matter and dark energy
• Quantum computing,
• Neutrino physics,
• String theory
• Particle physics, the Large Hadron Collider, the
  Higgs particle, Supersymmetric particles