FALL 2003 COLLOQUIA

DEPARTMENT OF PHYSICS AND ASTRONOMY

CALIFORNIA STATE UNIVERSITY

LONG BEACH, CA

Mondays, 11:30-12:45 in SLH-048

(Colloquium organizer: Mark Gross, mgross@csulb.edu)

Last updated 10/07/03

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September 1

LABOR DAY HOLIDAY – NO COLLOQUIUM

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September 8

Mladen Barbic

CSULB

http://nanofab.caltech.edu/users/mladen/website/index1.html

MAGNETIC RESONANCE IMAGING:

RACING TOWARD ATOMIC RESOLUTION

Over the last 30 years Magnetic Resonance Imaging (MRI) has advanced at a rapid pace. However, current demonstrated resolution in MRI is orders of magnitude away from the already achieved atomic resolution in electron microscopy, scanning tunneling microscopy, and atomic force microscopy. Atomic resolution three dimensional MRI, in my opinion, presents the ultimate challenge to an experimentalist pursuing the frontiers in solid state physics and biological imaging. As a new faculty member at the Department of Physics and Astronomy at the California State University, Long Beach, apart from the studies on magnetic and optical nanostructures, one of my principal goals will be to tackle this MRI challenge by developing ultra-high sensitivity MRI sensors and new imaging methodologies. I will present the work and ideas that have preoccupied me over the last two years in my quest to reach this imaging holy grail, and made me believe that we will one day get there.

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September 15

Helen Hansma

UC Santa Barbara

http://www.physics.ucsb.edu/~hhansma/

http://www.mrl.ucsb.edu/mrl/faculty/hhansma.html

SPIDER WEBS AND BACTERIAL BIOFILMS: PROBING

BIOMATERIALS BY ATOMIC FORCE MICROSCOPY

Why is spider silk so strong? How are the molecules of capture silk different from those of dragline silk? What happens to bacteria in biofilms when they are malnourished? Atomic Force Microscopy provides some answers to these questions.

The picture above shows a nanofiber of dragline silk (AFM image) superimposed on a spider web (digital photo) from the author's home.

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September 22

Lawrence Badash

Department of History, UC Santa Barbara

http://www.history.ucsb.edu/faculty/badash.htm

FROM SECURITY BLANKET TO SECURITY RISK:

SCIENTISTS IN THE DECADE AFTER HIROSHIMA

Aside from a number of early prophesies of abundant and cheap nuclear power, and increased supplies of isotopes for medical research, diagnosis, and therapy, visions of the Atomic Age were overwhelmingly troublesome in the aftermath of Hiroshima. Not only did nuclear Armageddon seem likely to many observers, the steps taken to enhance national security in the United States cast classes of citizens into the doleful category of "security risk." Scientists were among those feared--a stunning (and almost instantaneous) change from their perception in August 1945 as the nuclear wizards who brought World War II to an end. National security was the dominant factor in this transformation, but there were nuances to it. This paper presents various ways--such as mad, disloyal, and irrelevant--in which outspoken scientists were viewed in the United States.

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September 29

MILLER COLLOQUIUM

Edward L. Wright
UCLA Astronomy Department
www.astro.ucla.edu/~wright/intro.html

MAPping THE ORIGIN OF THE UNIVERSE

Full-sky CMB map

The Wilkinson Microwave Anisotropy Probe, launched on 30 June 2001, has released the data from its first year of observation at the Earth-Sun L2 Lagrange point. All-sky maps in five bands from 23 to 94 GHz give high signal to noise ratio detections of the cosmic microwave background anisotropy and the galactic foregrounds for angular scales between 0.2 and 180 degrees. The correlation between polarization and temperature anisotropies due to electron scattering in the surface of last scattering is seen at small angles, and a large angle correlation due to electron scattering after reionization in the Universe at a redshift of about 20 is also seen. The angular power spectrum of the anisotropy agrees well with the predictions of a flat, vacuum-dominated Lambda-CDM model.

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October 6

Chuhee Kwon

CSULB

http://www.cnsm.csulb.edu/faculty/ckwon/

My Current Researches:

SCANNING LASER MICROSCOPY of HIGH TEMPERATURE SUPERCONDUCTORS and ATOMIC FORCE MICROSCOPY of INSULIN FIBRIL

In this talk, I will introduce you to two of my current research topics; scanning laser microscopy of high temperature superconductors and atomic force microscopy of insulin fibril. Scanning laser microscopy is used to characterize the spatial non-uniformity in high temperature superconductor YBa₂Cu₃O₇ samples. We have observed non-uniformities due to inhomogeneous T_c in single-crystalline samples and due to large angle grain boundaries in coated conductors. We are also studying the formation and growth of insulin fibril using atomic force microscope. I will report preliminary findings of insulin fibril growth with respect to the incubation time.

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TO BE RESCHEDULED

JM Geremia

Caltech

QUANTUM NON-DEMOLITION MEASUREMENT:

FLIRTING with the FUNDAMENTAL LIMITS of DETECTION

According to the usual rules of quantum mechanics, physical systems evolve in an orderly, well-behaved manner, provided no one is looking. But, once measurement enters the picture, the state of the system can change in a violent, random and irreversible way- this is the essence of the familiar, yet bizarre, projection postulate. In recent years, however, it has become experimentally possible to watch an evolving quantum system in a less aggressive manner. So-called quantum non-demolition (QND) measurements work by entangling the system of interest with a probe particle and then measuring only the probe. This procedure allows continuous observation of the quantum system. It also opens the door to a new class of experiments capable of greater sensitivity than the “standard quantum limit” imposed by Heisenberg’s uncertainty principle. As an illustration, I will discuss our recent proposals for quantum noise limited detection of a magnetic field using a sample of laser cooled atoms. This talk will provide an introduction to the concept of entanglement as well as a modern perspective on how quantum measurement theory has advanced since the inception of the projection postulate.

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October 13

John O’Brien

USC Electrical Engineering

http://mpdg.usc.edu/

NANOPHOTONIC DEVICES

Two-dimensional photonic crystal devices take advantage of our ability to pattern the dielectric, through modern nanofabrication techniques, on a scale that is shorter than the optical wavelength at which the device operates. Patterning on this length scale allows us, in principle, to engineer the electromagnetic properties of photonic devices in microscopic detail. It is a serious challenge, however, to understand how to utilize this freedom to improve device performance, and this photonic crystal device technology is still relatively immature.

In this presentation we will discuss photonic crystal lasers and passive components. We have demonstrated both suspended membrane and sapphire-bonded photonic crystal microcavity lasers. These devices are optically pumped at and above room temperature. The patterning is done with electron beam lithography and a series of dry etching steps. We will also discuss our efforts to model the electromagnetic properties of these devices, using both finite-difference time-domain and finite element methods, and report on our experimental characterization of these lasers.

We have also demonstrated and will discuss two-dimensional photonic crystal waveguide components. Here we will also report on the comparison of the calculated and measured characteristics of these devices. Finally, we will also report on the demonstrations of waveguide bends and branches in these photonic crystal waveguides including a photonic crystal Mach-Zehnder structure.

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October 20

Jeanie Lau

HP Labs

http://www.hpl.hp.com/research/qsr

NANOSCALE SUPERCONDUCTIVITY AND ELECTRONICS

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October 27

Name Goes Here

Address goes here

webpage goes here

TITLE GOES HERE

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November 3

Hector Mireles

CSU Pomona

http://www.csupomona.edu/~hcmireles/#C

OBSERVATION OF MAGNETIC DOMAINS

WITH KERR MICROSCOPY

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November 10

Zoltan Papp

CSULB

webpage goes here

TITLE GOES HERE

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November 17

David J. Stevenson

Caltech Planetary Science

http://www.gps.caltech.edu/faculty/stevenson

TITLE GOES HERE

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November 24

Steven Furlanetto

Caltech

http://www.tapir.caltech.edu/#research

21 CM OBSERVATIONS OF NEUTRAL HYDROGEN AT HIGH REDSHIFTS

Recent observations of high-redshift quasars and of the cosmic microwave background have provided intriguing hints about the early phases of structure formation in the universe, but they leave many questions unanswered. Among the most important mysteries are the properties of the first sources of light and how (as well as when) these sources ionized the intergalactic medium surrounding them. One of the most promising ways to answer these questions is to measure the redshifted 21 cm signal from neutral hydrogen in the early universe. I will discuss several of the proposed measurements, including both ‘tomography’ of the high-redshift intergalactic medium and the ‘21 cm forest’ of absorption lines along the line-of-sight to bright radio sources, as well as their observational prospects with the next generation of radio telescopes.

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December 1

CHRIS CLAYTON

UCLA Laser-Plasma Group

http://www.ee.ucla.edu/labs/laser-plasma/people.html

PLASMA PHYSICS FOR ADVANCED ACCLERATOR TECHNOLOGIES:

RECENT EXPERIMENTS TOWARD PRACTICAL APPLICATIONS

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December 8

Jack Judy

Electrical Engineering, UCLA

http://www.ee.ucla.edu/faculty/bios/jjudy.htm

TITLE GOES HERE

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Information for speakers

Maps and directions are provided below. A typical audience consists of ~7-10 faculty and ~10 (mostly M.S.) students, and they tend to ask a fair number of questions both during and after the talk. The colloquia begin at 11:30 a.m. and we encourage speakers to end their presentations at 12:30 p.m., which will allow for 5-10 minutes of follow-up questions. If you have audiovisual needs other than a computer projector, please let me know in advance.

After the talk, a handful of us will take you to the ‘Chartroom’ for lunch, if your schedule permits. Typically lunch lasts about one hour.

MAPS and DIRECTIONS

Southern California Freeway system: http://www.formula.com/images/Map_SoCal.GIF

Freeway access to campus: http://daf.csulb.edu/maps/freeway/index.html

From 405 Fwy Southbound: Exit at Bellflower Blvd. Turn left from the off-ramp and then make an immediate right on Bellflower Blvd. Continue to State University Drive and turn left into campus.

From 405 Fwy Northhbound / 22 Fwy West / 605 Fwy South: Exit at 7^th Street and continue to Bellflower Blvd. Turn right at Bellflower Blvd and make another right at State University Drive.

Go to the Visitor Information Center on State University Drive, tell them your name, pick up your parking pass and park in Lot 1:

http://daf.csulb.edu/maps/parking/index.html (Employee Parking spaces are O.K.)

Another view:

http://daf.csulb.edu/maps/campus/sw.html

Walk (or ask for a ride) to the colloquium room, SLH-048:

http://daf.csulb.edu/maps/campus/oo.html