Instructor: Suzanne Amador Kane (X1198, KINSC L103)
Meets: MF 1:15-4:00, KINSC H106
Recitation Date & Location: Thursdays, 9am-10am, in H106 (our regular lab room) unless rescheduled (as of 8/30/05)
Textbook: Physics 326 Lab Manual (see Suzanne) & Gordon Squires, Practical Physics (available in the Bookstore)
BlackBoard: Additional Readings; Solutions to assignments and exams will be posted on the course Blackboard site. Problem sets are posted at the bottom of this website.

AAPT listserv on advanced lab materials

In Advanced Physics Laboratory, we will be doing one shared project on low noise electrical measurements & Johnson noise, and two project labs to be drawn from the following list. I've included some relevant papers and links so you can browse through these to see which ones interest you.

1) Microfluidics and Microcontact printing:
In this lab you will make your own microfluidics device and microstamps using PDMS (a polymer which can be imprinted with either flow cells or patterns for stamping) You will then do some simple projects using these ideas including: 1) Using microcontact printing to vary wetting (surface tension) properties of a device; 2) Using video microscopy to study low Reynolds number flows in microfluidics cells and see how they can be used to do sorting of molecules and chemical sensing. 3) Modeling the resulting flow patterns mathematically; and possibly 4) combining these projects to use microfluidic cells to sort particles, or to allow preferential binding of molecules to regions of a flow cell!

Here are some useful links: U. Wisconsin website about using PDMS to do microcontact printing; MIT Microfluidics project laboratory; Pierce Chemical Microfluidics Evaluation Kid for Microfluidics Chemistry: link to prefabricated microfluidics cells and instructions on easy experiments to do with them--made by Micronics, Inc. ; A Microfluidic Nanofilter: Filtration of Gold Nanoparticles ; Fall 2003 2-week short project lab poster on Microfluidics (Nathan Keim and Sebastian Mankowski); George Whitesides article on Flexible Methods for Microfluidics; A paper on A Flow Visualization Experiment for a First Course on Microfluidics by Shantanu Bhattacharya et al.

2) Laser Tweezing
In fall 2003, our advanced lab teams successfully constructed a working laser tweezer, used it to manipulate microspheres, calibrated it (approximately) using the Stokes drag force on polystyrene spheres, and attempted to performed experiments on bacteria. This next installation will involve improving the optical setup, using the fluctuation spectrum of trapped particles to perform a precise force calibration, then moving on to doing experiments. Ideas include: motility assays of mutant strains of E. coli, force-extension measurements of biological molecules and making photonic crystals.

Mara Prentiss's group website on laser tweezers for junior lab; Mark C. Williams Northeastern University Laser Tweezer Lab Manual and background on laser tweezing; Applications ideas from P.A.L.M. Microlasers

3) Nanotube Synthesis and AFM imaging
You will synthesize using chemical vapor deposition carbon nanotubes and image them at the nanometer-scale using atomic force microscopy (AFM). Working with the instructor, you will research and formulate a new strategy or question to answer about ways of synthesizing carbon nanotubes or controlling their properties, and examine how different protocols affect the resulting yield, number of walls, and lengths of the resulting samples.

Fall 2003 2-week short project lab poster on Nanotube Synthesis and AFM imaging (Amy Perlman and James Sundquist); Nathan Keim and Collin Rich's writeup on carbon nanotube synthesis.

4) Chaos in Electronic Circuits
Electrical circuits can be constructured to display fascinating behavior as a consequence of their nonlinear response functions. These exercises allow students to construct and characterize some classic operational amplifier labs enroute to constructing more complex circuits that demonstrate in a particularly elegant way chaotic responses.

5) Quantized conductance in nanocontacts
In general, construction of nanoscale electronic circuits is a challenging exercise requiring specialized equipment. However, it's possible to see quantum mechanical effects on conductance in a simple circuit consisting of small-scale contacts established between two gold wires brought into loose contact. This lab allows you to use sensitive low-noise electronic measurements to see the consequences of quantum mechanics for such systems, which result in quantization of the conducting properties of these systems.

Donald Candela at U. Mass. Amherst is doing this as an instructional lab in their Physics 26 course; Florida State University link on teaching this lab.

Papers on quantum nanocontacts: "An undergraduate laboratory experiment on quantized conductance in nanocontacts"
E. L. Foley, D. Candela, K. M. Martini, and M. T. Tuominen, Am. J. Phys. 67, 389-393 (1999); Costa-Krämer, et al., "Nanowire formation in macroscopic metallic contacts: quantum mechanical conductance tapping a table top", Surface Science 342, L1144 (1995). "Ballistic electron transport through a narrow channel is quantized", Seach and Discovery section of
Physics Today, November 1988.D. F. Holcomb, “Quantum electrical transport in samples of limited dimensions”, American Journal of Physics 67, 278 (1999). Theory by Charles Stafford (Physics, U. Arizona) relevant to nanocontacts measurements.

6) Quantum Dots--synthesis and characterization
In this lab you will synthesize tiny nanoscale spheres of semiconductors that act as 3D quantum wells. This type of "quantum dot" has interesting electronic bandstructure, and hence spectroscopy properties of great physical interest and scientific utility. Not only will you synthesize the quantum dots, you will also use dynamic lightscattering to measure their sizes and spectroscopy to explore their optical absorption and emission properties.

Papers on quantum dots: Max G. Lagally. 1998. "Self-Organized Quantum Dots," Journal of Chemical Education vol.75, no. 3, pp. 277-279. Elizabeth M. Boatman, George C. Lisensky, and Karen J. Nordell, “A Safer, Easier, Faster Synthesis for CdSe Quantum Dot Nanocrystals,” submitted to J. Chem. Ed.; "Spectroscopic Analysis of Semiconductor Colloids",
Chandler, RR, Bigham, SR, Coffer, JL, J. Chem. Ed., 1993, 70, A7. 69. We used this website to get our protocols for synthesizing the CdSe quantum dots. We purchased our kit of many different color quantum dots from Evident Technologies so we could perform dynamic light scattering (for sizing), UV-vis spetra (to see absorption spectra) and fluorimeter measurements (to see the photoluminescence spectra). Another good reference is: Quantum Dot Corporation;

7) Muon Physics

This sequence of experiments gives you experience with particle detectors and allows you to explore the physics of an exotic fundamental particle naturally produced by cosmic ray showers. See the description of the apparatus and experiments at TeachSpin

8) Tubulin Polymerization Dynamics

Tubulin is an important structural protein found widely in nature. Using dynamic light scattering and spectroscopy, you can explore the physics of polymerizatoin and aggregation in this biophysical experiment. (Short experiment under development)

Read about tubulin and its assembly at Cytoskeleton.com

9) Computed Tomography and Radiography in Medicine

In this short experiment under development, you use visible light (not x-rays) to perform computed tomography--a technique that allows one to image an object in 3 dimensions. When finished, this experiment will be available to other students interested in medical physics.

Course materials Online (We will not use Blackboard for most postings)

Websites of interest

Fall 2003: 2-week short project lab poster on Microfluidics (Nathan Keim and Sebastian Mankowski)

Fall 2003 2-week short project lab poster on Nanotube Synthesis and AFM imaging (Amy Perlman and James Sundquist)

Advanced Lab Photos from last offering!

Lab Manual for Nanoscale Science and Technology (University of Wisconsin's MRSEC)
Biophysical Society's listing of biophysics educational opportunities (including instructional labs) and their techniques website
MIT Junior Lab projects