Involvement of undergraduate students at various levels and from different departments is an integral part of the Applied Optics group. Undergraduates typically work in the group for a year of longer on independent projects, but in close collaboration with a graduate student or postdoc. The projects are usually components of our larger research projects. Occasionally, the projects are the senior thesis project of the student.

Students are usually supported by REU grants from the National Science Foundation or fellowships. Applied Optics students have consistently done excellent research work and have been recognized by undergraduate research awards at UCSC. We are always looking for academically outstanding and highly motivated undergraduates to get research experience in our lab.

Below is an overview of projects that have been completed by undergraduates over the past few years.

Pulse Generator for Single Photon Counting
(Kevin Louchis, EE, 2008)

*Deans Award for Undergraduate Research 2008

The time-dependent emission intensity of a fluorescent effect can be studied by measuring and compiling the time difference between a photon emission with a low probability of detection and an electric pulse over many regular excitations. In order to compute and compile the time differences the TimeHarp 200 PCI card is used. The TimeHarp 200 needs an external pulse to perform the computations. Kevin designed and built the electric pulse generator required to provide the synchronization pulses from bipolar junction transistor technology. This project consisted of designing and laying out the design in computer software, assembling the circuit on circuit board, as well as machining a metallic housing for the circuit.

Near-field Polarization Characterization
(Wilhelm Melitz, EE, 2007)

*Dean's and Chancellor's Awards for Undergraduate Research, Huffman Prize 2007

The highest optical resolution can be achieved with near-field detection where a small aperture is brought very close to the surface of interest to detect any light emanating from the sample. In order to use this prinicple for characterization of magnets, the effect of the near-field aperture on the polarizaton of the light needs to be known. In his senior design project, Wil characterized the polarization properties of a new type of microfabricated near-field tips. He was able to show that the polarization properties depend strongly on the tip that is used. In addition, he had to machine several components to replace standard parts in the near-field microscope.

Waveguide Loss Measurements
(Alex Polyakov, Physics, 2007)

The loss of power as light travels along a waveguide can be measured in different ways, some of which destroy the waveguide in the process. A non-invasive way of measuring waveguide loss is to detect the amount of light scattered from the top of the waveguide as a function of position. Alex used a high-resolution optical microscope with a CCD array detector to record the scattered light across ARROW waveguides and extract the waveguide loss coefficients from the data. This project included building a setup to investigate the waveguides under the microscope, taking and analyzing the data, and writing Matlab code to help with the data analysis.

Differential Photodetector for Magneto-Optics
(Wesley Zuber, EE, 2006)

(Dean's Award for Undergraduate Research 2006)

Magneto-optical measurements use changes in polarization to determine the magnetic state of a material. If the material is a tiny nanomagnet, these measurements become very challenging and detection sensitivity needs to be optimized. A good way for sensitive magneto-optical detection is to split light into two polarization components and send it to two photodetectors whose signals are subtracted. Wesley built such a differential photodetector including the physical design, circuit design, testing and trouble shooting.

Rubidium Spectroscopy Setup
(Palmer Taylor, Physics, 2005)

(Dean's Award for Undergraduate Research 2005)

The goal of this project was to build a setup to measure the hyperfine structure of the absorption spectrum of rubidium vapor. The project including setting up optical elements, dealing with tunable lasers, and analyzing light transmission through atomic vapor cells as a function of wavelength. Palmer's work which also comprised his senior thesis was the basis for our future demonstration of the first integrated optical atomic spectroscopy cell on a chip.

Far-field Waveguide Mode Measurement Setup
(Senait Gebredingle, EE, 2004)

(Dean's and Chancellors' Awards for Undergraduate Research 2004)

The spatial distribution of power in the output of an integrated optical waveguide can be measured in different ways. Near-field measurements right at the facet provide a direct image of the mode, but are experimentally complex. A far-field image taken at a distance away from the waveguide is easier to carry out and yields the Fourier transform of the mode shape which can then be traced back to the actual image. This project entailed building a far-field detection setup, in which a photodetector is scanned in a two-dimensional plane to record the spatial image of the waveguide output. This work included building and calibrating the scanning setup, writing LabView code for computer control, and testing the instrument by recording and analyzing the output mode of different waveguides. This was also Senait's senior design project.

Intersubband Spectroscopy of Quantum Dots
(Philip Measor, EE, 2004)

(Dean's and Chancellors' Awards for Undergraduate Research 2004)

The goal of this project was to adapt software for electronic band structure calculation for the C programming language and use the code to analyze optical intersubband transitions in semiconductor quantum dots. In addition, Philip carried out infrared absorption measurements on CdTe quantum dots in a Fourier Transform Infrared Spectrometer. This work involved modifying the sample space of the FTIR, working with semiconductor quantum dots, and analyzing the resulting spectra. His work was the basis of his senior thesis and also lead to a conference presentation in Switzerland which he co-authored.

Optical Autocorrelator
(Steve Kuhn, CE, 2003)

(Dean's Award for Undergraduate Research 2003)

An optical autocorrelator is an apparatus that allows to measure the duration of short optical pulses from a femtosecond laser. This project consisted of building an autocorrelator from scratch, careful alignment of all parts and testing the instrument using pulses from a femtosecond laser. In addition, Steve wrote a LabView program for automated pulse characterization. This work was the subject of his undergraduate thesis.

Magneto-Optic Kerr Effect Setup
(Heather Levin, EE, 2003)

(Dean's Award for Undergraduate Research 2003)

This project entailed building a simple magneto-optic setup that detects the polarization change of light as it is reflected from a magnetic surface. Tasks included setting up and aligning the optical elements, writing LabView code for automatic control, and testing the setup with various magnetic materials. The setup formed the basis for later experiments on single nanomagnet switching and was also developed into a lab experiment for our undergraduate class EE145 (properties of materials).