After completing mandatory courses, qualifying exams, and the necessary paperwork, Jami Valentine (pictured left) can finally see the light at the end of the tunnel. Now she's in the homestretch, 6 months from getting her Ph.D. But before she earns her degree, she has to defend the scientific work she's been doing for the last 6 years. "I try to stay calm," the Philadelphia native says with a laugh, "and not freak out about it because it's a major step--everything I've been working [toward] for so many years."

Valentine, scheduled to defend her dissertation in March 2006 at Johns Hopkins University's (JHU) Department of Physics and Astronomy, shares her graduate school experiences and talks about her preparation for her thesis defense. She looks forward to completing this last hurdle. Doing so means she's one step closer to her ultimate goal--becoming a physics professor.

A Marathon, not a Sprint

Valentine's science journey began in junior high school when she joined the Philadelphia Regional Introduction for Minorities to Engineering (PRIME) program. PRIME's summer preparatory classes, she says, encouraged her to study science. She jokes that the program's instructors "brainwashed us into thinking we should all major in engineering or mathematics or some hard science." After finishing at Dobbins Technical High School, she majored in physics at Florida Agricultural and Mechanical University (FAMU), in Tallahassee.

In 1996, Valentine graduated from FAMU and left to pursue a Ph.D. in physics at Brown University. But the transition from a southern historically black university to an elite northeastern university, coupled with what she calls "taking on too much," overwhelmed her. "I didn't do as well as I could have there," she says, "and I ended up not passing the qualifying exams."

Valentine finished her master's degree, then took her graduate advisor's advice. "I think you should apply to different schools," he said, "and continue to pursue this degree . . . I think you can be a good scientist." This time she sought programs that provided more support along with top-level research. She chose Hopkins, with its relative wealth of African Americans and women in graduate science programs. "There's a better sense of community here," Valentine asserts. When she arrived, JHU had two female professors in the physics department and approximately 30 female graduate students. Brown had no female professors and only 10 female graduate students.

Developing New Technology

At Hopkins, Valentine tests rare earth metals with the hope of finding a material to create a faster, higher storage capacity hard drive for computers by exploiting a phenomenon known as 100% spin polarization--electrons are either "spin up" or "spin down." With connectors made of material with 100% spin polarization, electrons maintain their spin moving from one circuit element to another unlike typical circuit connectors that flux as current passes through. Because there will only be one spin channel in the connectors, theoretically, changing the spin of the magnetic elements provides a subatomic level of control.


A magnetron sputtering chamber.

The lab's custom built probe--a magnetron sputtering chamber--performs 50 to100 point contact Andreev reflection (PCAR) measurements at 4 Kelvin, which measures the value of spin polarization for the metals being tested. It's just one of several steps used to find materials--in Valentine's case, rare earth metals--capable of building a better hard drive.

The "Write" Plan for a Thesis Defense

Graduate students in physics at Hopkins must pass a series of exams--four written exams during their second year--to continue as doctoral candidates. The preliminary oral exam follows soon after, and this is followed, finally by a graduate oral exam. The last serves as a thesis proposal, after which candidates are awarded the master's degree and advance to Ph.D. candidacy.

The thesis defense in physics at Hopkins has two components. First comes a public seminar where the candidate makes a 40-60 minute presentation. The second part, the formal defense, is reserved for the defense committee and the student and can last as long as a couple of hours.

By the time of her defense occurs, Valentine will have spent 9 months writing her dissertation. "Different students approach this different ways," Valentine says. While one colleague has been diligently writing her dissertation throughout her graduate career, others cram, she says, for the last three months.


Valentine stands next to a piece of equipment she uses often, a four-circle x-ray diffractometer.

Valentine spends about 3 hours in her 10-to-12 hour work day writing her dissertation. When it's finished, the thesis must be approved in writing by the thesis defense committee--which, at Hopkins, is composed of five members, including two from outside the department--before a student is allowed to defend. "There's nothing that you can hide from them," Valentine says with a healthy sense of paranoia, "because they have everything in front of them." Completing the introduction and background first has given her a solid starting point and the confidence to help her beat her problem with writer's block.

The rest of Valentine's time--or much of it--is spent reviewing reference materials, experimental data, and annual reports. During this time she anticipates the defense committee's questions, hoping to have answers ready when the defense committee asks them. She talks often with her advisor, who prompts her to consider possibilities she might have missed. She's even designing a few final experiments to strengthen her conclusions. The process is designed to fill in any "large, gaping holes." As part of this process, Valentine says, she often finds herself putting herself in her advisor's shoes to figure out how he thinks and what questions he is likely to ask.

Eventually, Valentine hopes to be in her advisor's shoes permanently, as a physics professor, and says JHU's diverse scientific environment provided her with the support she needed. Thinking ahead to the day she runs her own lab, Valentine hones her networking skills by maintaining a database of minority women physicists and recently attended the Second International Conference on Women in Physics in Rio de Janeiro. "I think that it would be wonderful if we can get to the point where every physics department had at least one woman physics professor," Valentine concludes.

Clinton Parks is a staff writer for MiSciNet and may be reached at cparks@aaas.org.

Clinton Parks is a writer for MiSciNet and may be reached at cparks@aaas.org.