The Royal Swedish Academy of Sciences has awarded the

1
The Royal Swedish Academy of Sciences has awarded
the Nobel Prize in Physics for 2005 Roy J.
Glauber (Harvard University)"for his
contribution to the quantum theory of optical
coherence" John L. Hall (JILA) Theodor W.
Hänsch (MPI für Quantenoptik and LMU)"for their
contributions to the development of laser-based
precision spectroscopy, including the optical
frequency comb technique".
2
Wesleyan University Physics Faculty
Without pictures Amarjeet Bhullar Jose Rivera
Rojas Jack McIntosh Mark Shapiro
?
3
Wesleyan University Graduate Students
Without pictures Josh Eddinger Iulian
Clappa Dan Blum Denis King Yeung
Chan Tomoko Ishihara Magda Coman Benedikt
Greipl
4

• Tom Morgan
• David Wright, Jon Lambert, Heric Flores
• Jack DiSciacca, Gim Seng, Tito Cuadrado
• Recurrence Spectroscopy

5
(No Transcript)
6
(No Transcript)
7
(No Transcript)
8
(No Transcript)
9
(No Transcript)
10
(No Transcript)
11
(No Transcript)
12
(No Transcript)
13
(No Transcript)
14

• Brian Stewart
• Paula Matei, Steve Coppage
• Nasim Khoshkou, Jamie Macia
• Molecular Collisions

15
(No Transcript)
16
Differential Scattering Cross Section of
Rovibrationally Inelastic Processes
Optical-optical double resonance experiments can
be employed to obtain information on inelastic
differential scattering cross sections. We are
studying rovibrationally inelastic processes in
the Li2 (A) noble gas system. One of our goals
is to look for experimental evidence of a novel
vibrational transfer mechanism that involves
impacts with the side of the molecule, resulting
in backwards scattering even at small ?j. The
experimental lineshapes are compared with
lineshapes simulated using differential cross
sections calculated from an ab initio potential
surface.
17
(No Transcript)
18
(No Transcript)
19
Observation of exchange reactions in a heat pipe
oven 7Li2(A1Su) 7Li ? 7Li 7Li2(A1Su)
Odd ?j changes in rotational quantum number of
homonuclear diatomic molecules are forbidden in
inelastic collisions permitted in exchange
reactions. Using a heat pipe oven and Laser
Induced Fluorescence, we produce Li2 molecules in
the A state with v2, j19. We observe odd ?j
products in excited state 7Li2(A1Su) collisions
with 7Li atoms. Future research should enable us
to determine rate constants for this reaction and
compare the dynamics to collisions with neutral
partners, such as Ne.
20
(No Transcript)
21
(No Transcript)
22

• Lutz Hüwel
• Hong Chen
• Mike Dacey, June Kang
• Molecular Photophysics

23
TG
GPIB
PC
MCP
DG
trigger from YAG laser
TOF
MBS
BC
HWD
BF
DL-1
DL-2
M
ExperimentalSetup
24
Linear Time-of-Flight Spectrometer
(Wiley McLaren type )
25
(No Transcript)
26
The semi-classical model for the dissociative
autoionization

• The ionic core
• moves in a classic motion
• starts autoionization
• gains kinetic energy
• starts dissociative autoionization
• dissociative autoionization stops

Autoionization occurs R0ltRltR1 Indirec-
dissociative ionization occurs R1ltRltR2
27
Model calculation compared with Experimental
results
28
(No Transcript)
29

• Fred Ellis
• Josh Eddinger
• Quantum Fluids

30
Superfluid Acoustic Amplification
Liquid Helium at low temperatures is a quantum
liquid of Bose particles. Below 2.17 K, in the
superfluid state, the fluid acts as if all of the
particles are in the ground state, even though
other mechanical features of the fluid (like
sound waves) might not be in the ground state.
This coherence of the particles results in an
analogy between superfluid helium and a laser
LASER
Superfluid Conversion
Atoms are stimulated by the photon field to lower
their energy and add a coherent photon.
Atoms are stimulated by the de Broglie field to
condense and add a coherent de Broglie wave.
31
Suppose that the superfluid is part of an
oscillatory wave motion. The de Broglie wave
field has an acoustic oscillation character and a
superfluid particle-collection character. These
characteristics are separate attributes of the
quantum system and allow the particles to be
removed while preserving the acoustic gain.
A condensing vapor thus deposits acoustic energy
into a wave mode even as the particles themselves
flow out of the wave region to be returned to the
vapor source. If the condensation rate (gain) is
high enough, the wave mode will self-oscillate,
just as a laser does with sufficient cycling of
excited atoms theoretically. This
exciting experiment is almost ready to go!
32

• Rollie Rollefson
• Zara Acosta 05
• Adsorbed States

33
MCM-41 is a high surface area (725 m2 per gram)
powder with very uniform cylindrical pores. The
Isotherm shows the amount of N2 gas in the sample
versus the reduced pressure. 
34
MCM-41 pore size distribution derived from
measured isotherm
35

• Greg Voth
• Jim Johnson, John Perez
• Fluid Dynamics and Soft
• Condensed Matter

36
Voth Group 2005

• Jim Johnsonfinished design and construction of a
  flow between oscillating grids for measurements
  tracking particles in turbulent flows.

• John Perezcompleted an extensive set of
  measurements on the time evolution of 2D granular
  gasses. His measurements revealed substructure
  in granular shocks and promise

Y
time
37
Voth Group 2005

• Dominick Stich designed and successfully tested
• a digital circuit for real time image processing
• Undergraduate honors theses
• Naomi GoldensonSlope stability of granular
• materials under external vibration
• Dennis ChanRelationship between particle
• accelerations and diameter in turbulence
• Other highlights
• Prof. Voth received a Sloan Research
  Fellowship.
• The 3rd NY/NE Granular Materials Workshop was
  hosted here at Wesleyan in June.

38

• Jack McIntosh
• Paleontology

39
http//www.enchantedlearning.com/subjects/dinosaur
s/glossary/Fossilhunters.html
The Top Paleontologists and Dinosaur Hunters of
All Time
McINTOSH, JACK Dr. Jack McIntosh is currently
the foremost expert on sauropods. McIntosh
corrected the naming of many sauropods originally
named by O.C. Marsh and E.D. Cope. McIntosh has
also done much to popularize the use of the name
Apatosaurus (rather than Brontosaurus). His most
important contribution to paleontology was
identifying the correct skull for Apatosaurus in
1975 (fifty years earlier, Marsh had put a
Camarasaurus skull on the Apatosaurus' body).
40

• Reinhold Blümel
• Computational Physics

41
Solution of the finite quantum square-well
problem
42
(No Transcript)
43
R. Blümel "Analytical solution of the finite
quantum square-well problem",  J. Phys. A Math.
Gen. 38, L673-L678 (2005).
A. S. Bhullar, R. Blümel, and P. M. Koch Ray
splitting with ghost orbits explicit, analytical
and exact solution for spectra of scaling step
potentials with tunneling J. Phys. A Math.
Gen. \bf 38, L563--L569 (2005).
C. Vaa, P. M. Koch, and R. Blümel, Weyl formula
Experimental test of ray-splitting and corner
corrections'', accepted for publication in
Physical Review E (2005)
A. S. Bhullar, R. Blumel, and P. M. Koch, Ghost
orbit spectroscopy'', submitted to The Physical
Review E (2005). R. Bl\"umel and I.
Garrick-Bethell, Quantum mechanics of the
dynamic Kingdon trap'', submitted to The Physical
Review A (2005).
44

• Francis Starr
• Andrew Rahedi
• Computational Soft Condensed Matter Physics

45
Starr Lab Facilities

• Cluster of off-the-shelf PCs working together
• Cost efficient 500-1500 per computer
• Fast 50 computers 50 times the speed of a
  single PC! (for independent tasks)
• Hardware
• Athlon CPUs each at equivalent of 3GHz
• Memory 512MB-4GB per machine
• Disk Server 1.4 TB of storage
• Software
• Linux with MOSIX add-on
• Resources are shared transparently
• Automatic and dynamic load balancing
• SCIENCE
• Numerical Experiments
• Soft materials, nanotechnology

46
Assembly/Properties of Polymer-Nanoparticle
Composites
Bundle formation by semi-flexible rods
(nanotubes) in polymer matrix

• Use simulations to
• - Characterize and develop materials
• Aid experiments
• Basic physics of reversible clustering

47
Self Assembly and Gelation of DNA
1. Control sequencing of bases
2. Link single strands into macromolecule
T
A
G
C
C
3. Spontaneously form complex networks
G
A
T
T
A

• We get out
• - Mechanisms for assembly
• Physics of gels
• New materials (drug storage, etc)

G
C
C
G
T
A
48
Liquids and the Glass Transition
Liquid Water distinct liquid phases at low T!
Low Density / Pressure (Ice-like)
High Density / Pressure

• Supercooled Liquids/Glasses
• How do molecules rearrange?
• How does preparation affect properties?
  (non-equilibrium statistical mechanics)

Rearranging molecules in a nearly fixed
background liquid
49
CURRENT GROUP
Boris Lukanov (04)
Scott Knauert (07)
Dan Slimmon (07)
not pictured Henry Tan (08) Jose
Rivera-Rojas (postdoc)
Andrew Rahedi (grad student)
50

• Tsampikos Kottos
• Moritz Hiller
• Nonlinear Dynamics and Chaos

51
Challenging Kubo formalism for Chaotic Quantum
Systems
Consider a large collection of mesoscopic rings
that are driven by an electromagnetic field, such
that there is a time dependent magnetic flux F(t)
which creates an electro-motive-force (EMF)
-dF/dt in each ring. If Ohms law applies the
induced current is I -G dF/dt and consequently
the rate of energy absorption is given by Joules
law as G (dF/dt )2 where G is called the
conductance. Conventionally G is related to the
first-order transitions that dominate the energy
absorption in the limit of weak driving amplitude
such that Fermi Golden Rule (FGR) is applicable.
Then the absorption is determined by the matrix
elements Inm to make a transition from the
initial level (m) to some other level (n).
Summing over all transitions we get the Kubo
formula
where w is the frequency of the driving, and
ltlt...gtgt stands for a statistical average of
either disorder configurations, or over the
distribution of geometrical parameters. or over
some energy range around the Fermi energy. Kubo
formula (1) has been used in order to calculate
the conductance of diffusive rings and it leads
to the Drude formula.
52
Challenging Kubo formalism for Chaotic Quantum
Systems
53
Quantum pumping in closed mesoscopic devices
Consider an Aharonov-Bohm ring with a Fermi sea
of non-interacting spinless electrons. Assume
that the ring is either disordered or chaotic,
and that the temperature is known. In such a case
the ring has a well defined Ohmic conductance
Gohm. This means that if we change the magnetic
flux through the ring, then the charge which is
transported is dQ -GohmF.
54
Parametric evolution of eigenstates of chaotic
mesoscopic systems Beyond perturbation theory
and semiclassics