Experiment in Lab-III

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Available projects in Fall 2011

One has to obtain 5 or 6 stars () by choosing amongst these experiments. Experiments 3.1 to 3.4 will be supervised by Dr. Mumtaz Sheikh. So contact him directly and inform me of the status for purposes of book-keeping. Besides these experiments, I can assign you experimental research tasks on the fly. Of course, you will be given the appropriate number of stars for any task you are assigned in the lab and I will let you know the weightage too.

Optical Magnus Effect (3.1)

This can be considered to be an inverse effect to Berry’s phase in an optical fiber. By switching the chirality of input polarization, the speckle pattern of a laser beam transmitted through a multimode fiber can be observed to undergo an angular shift.
Further Readings and References "Optical Magnus Effect", A. V. Dooghin, N. D. Kundikova, V. S. Liberman and B. Ya. Zel'dovich, Physical Review A 45, 8204-8208 (1992).

Radio Frequency (RF) spectrum analyzer using Acousto-Optic modulators (AOMs) (3.2)

The aim of this project is to build a RF spectrum analyzer using AOMs. As a first step, a basic spectrum analyzer can be built by using one AOM together with a laser and collimation optics. The more challenging part would be to build an advanced spectrum analyzer using two AOMs in an interferometric configuration that would considerably improve its dynamic range.
Further Readings and References "Interferometric spectrum analyzer", A. Vander Lugt, Applied Optics 20, 2770-2779 (1981).

Optical Bistability (3.3)

Optical bistability occurs in a system in which there are two stable values of the output intensity for one value of the input intensity and the two values can be made to switch between each other. This phenomenon can be demonstrated using electro-optics.
Further Readings and References "Optical Bistability: An Undergraduate Experiment", W. P. Greene, H. M. Gibbs, A. Passner, S. L. McCall, and T. N. C. Venkatesan, OPTICS NEWS 6, 16-19.

Sagnac Effect (3.4)

The Sagnac effect is an interference phenomenon that is elicited by rotation and can be demonstrated using a ring interferometer. It is the electromagnetic equivalent of the mechanics of rotation and is the principle behind laser and fiber-optic gyroscopes.
Further Readings and References "Optics", page 441-442, E. Hecht, 4th Edition (Preason Education).

Birefringence of cellophane tape (3.5)

The birefringence of ordinary cellophane tape is measured using polarized light from different laser sources. Concepts of linear, elliptical and circular polarization and their description in terms of Jones vectors is required. We can even produce different colours using this property.
Further Readings and References "On producing colours using birefringence property of transparent, stretched, colourless cellophane tape", S.J. Edwards and A.J. Langley, Leonardo 14, 187 (1981).

"Birefringence of cellophane: Jones representation and experimental analysis", A. Belendez, E. Fernandez, J. Frances, C. Neipp, European Journal of Physics 31, 551 (2010).

Sonoluminescence (3.6)

A flask is driven into acoustic resonance with the help of piezoelectric transducers. The bubbles trapped in the water glow. The effect is called sonoluminscence. This project involves building a circuit to generate the high voltage for the transducers, measuring the resonance and observing the glow. Its a challenging project.
Further Readings and References Sonoluminescence report from Techmind.

"Sonoluminescence", Advanced undergraduate experiment from University of Toronto, Physics Department.

Thermal expansivity of solids (3.7)

The goal of this project is to measure the thermal expansivity of different materials such as metals (aluminium, copper, brass), wood and plastics (plexiglass). What happens to glass as it cooled to near very low temperatures? Could you monitor the initiation of cracks induced by thermal stress?
Further Readings and References

"Measurement of thermal expansion coefficients using a strain gauge", J.N. Fox, American Journal of Physics 58, 875 (1990).

Magnetic and electrical properties near phase transitions (3.8)

The phase transition from the ferromagnetic to the paramagnetic state is of second order, and is defined by critical exponents. This experiment aims at determining these critical exponents. Furthermore, the resistivity of a ferromagnet changes near the critical point owing to the high permeability and hence the reduced skin depth. This experiment aims at understanding the electrical and magnetic beahviour near the phase transition points.
Further Readings and References

"Curie point of ferromagnets", Y. Kraftmakher, European Journal of Physics 18, 448 (1997).

AC Jospehson effect (3.9)

With the help of a GHz (microwave) frequency source, rf radiation is applied to the Jospheshon junction, resulting in stair-case I-V characteristics. These are called Shapiro steps and are a direct manifestation of the AC Josephson effect. One may use these steps to determine the Planck's constant.
Further Readings and References

"Shapiro steps observed in a dc superconducting quantum interference device with multiple junctions in each arm", L. Chen, P. Chen, C.K. Ong, Applied Physics Letters 80, 1025 (2002).

Frustrated total internal reflection (3.10)

With the help of a coherent light source, i.e. a laser, and prisms it is in fact possible to demonstrate the phenomenon of frustrated total internal reflection. Quantitatively accurate results are attainable. The prisms are placed on translation and rotation stages.
Further Readings and References

"A simple demonstration of frustrated total internal reflection", Z. Voros, R. Johnsen, American Journal of Physics 76, 746 (2008).
"A new method to demonstrate frustrated total internal reflection in the visible band", Y. You, X. Wang, S. Wang, Y. Pan, J. Zhou, American Journal of Physics 76, 224 (2008).

Physics of blood flow (3.11)

Blood flow is a complicated biological systems phenomenon. At the basis of this flow, are simple fluid mechanical notions such as Bernoulli's and Poiseuille laws. This project entails a simpler channel arrangement that can illustrate the basic hemodynamic properties such as effects of vasodilation, vasoconstriction, external pressure on arteries and vessel obstruction. Involves several exciting concepts in fluid mechanics.
Further Readings and References

"An experimental approach to the fundamental principles of hemodynamics", F. Pontiga, S.P. Gaytan, Advanced Physiological Education 29, 165 (2005).

Speed of ultrasound waves measured by diffraction (3.12)

Ultrasound waves are generated by a transducer driven by a crystal oscillator. The medium is carbon tetrachloride or distilled water placed in a metal tank. The standing waves of compressions and refractions produce a diffraction grating through which incident light is diffracted. The phenomenon is used to measure the speed of ultrasound waves in the liquid.
Further Readings and References

"Undergraduate experiment to measure the speed of sound in liquid by diffraction of light", D. A. Luna, M.A. Real, D.V. Duran, American Journal of Physics 80, 874 (2002).
"Experimental physics for students", page 47-49, R.M. Whittle and J. Yarwood, (London, Chapman and Hall).

Fluorescence from chlorophyll and other commonly available dyes (3.13)

Chlorophyll is extracted from spinach leaves and characterized by UV-VIS absorption spectroscopy. (Facility is available in the chemistry lab.) The experiment requires the examination of fluorescence and its dependence on concentration as well as the investigation of fluorescence quenching and depolarization.
Further Readings and References

"Laser experiments for beginners", page 143-178, R.N. Zare, B.H. Spencer, D.S. Springer, M.P. Jacobson, (University Science Books, California).

Computer based Lock-in Amplifier (3.14)

Lock-in amplifier is an essential component in experimental sciences research. In experiments, we repeatedly use lock-in amplifier to measure the response of a system which is feeble or is buried in excessive noise. In this project, we shall develop a home based lock-in amplifier using National Instruments DAQ cards for signal acquisition. Computer controlled interface is provided by LabVIEW.
Further Readings and References

"The lock-in amplifier: A student experiment", page 569-572, Richard Wolfsan, Department of Physics, Middlebury College, Middlebury, Vermount 05753.

Ferromagnetic Phase Transition (3.15)

A direct method to study the transformation of ferromagnetic materials into paramagnetic at Curie temperature is developed and critical exponent is found. One of the main aim of the experiment to observe the change in hysteresis loop at Curie temperature.
Further Readings and References

"A Direct Method for Viewing Ferromagnetic Phase Transition", The Physics Teacher, 32, May (1994), page 304-305, Chin-Shan Lue.

Building an NMR spectrometer (3.16)

The ultimate goal of this long project is building an NMR spectrometer with the magnet, electronic detection circuitry and software. We like to see the FID (fourier induction decay) signal from a test tube containing water and should be able to measure the relaxation times of the spins.
Further Readings and References

Contact me directly for references.

X-ray spectrometry (3.17)

This project involves working with an X-ray fluoremeter system, in particular, performing the following experiments:
  • X-ray spectrometry of samples, including thin film analysis
  • Verification of Moseley's law
  • Designing an experiment for the Compton Effect
  • X-ray diffraction of sodium chloride
Further Readings and References

Contact me directly for references.

Verification of the Zeeman Effect (3.18)

The student will verify the Zeeman effect using mercury vapor placed inside a magnetic field. a Fabry-Perot interforemeter will be used for resolving the wavelengths.
Further Readings and References

"The Zeeman Effect", B. Topper, unpublished.
"The Zeeman Effect", A. Povilus, unpublished.

Select Experiments in Quantum Optics (3.19)

There is vacancy for one student in helping out in the experiments on quantum optics which involve:
  • single photon detection and correlation function of sub-Poissonian light
  • quantum teleportation
  • quantum key distribution
Further Readings and References

Contact me directly for references.

Final touches to the Experiment involving Detection of Nuclear Radioactivity (3.20)

We will engage one student in finalizing the hardware and software, as well as the pedagogical literature for the Experiment titled Natural radioactivity and Statistics, numbered 1.10, which is a freshmen experiment to be offered to the forthcoming clases.
Further Readings and References

Contact me directly for references.

Measuring Electrical Transport and Dielectric Properties (3.21)

Students will be required to:
  • measure the electrical conductivity as a function of temprature
  • measure the dielectric constant as a function of frequency and temperature
  • build an assembly for meausurement of the Hall effect in various kinds of materials.
Further Readings and References

Contact me directly for references.

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