March 6, 2009
Yuchen Zhou didn't plan on being an engineer.
In fact, when the 2005 graduate originally enrolled at Carnegie Mellon, he planned to pursue a PhD in physics, a natural continuation of the undergraduate degree in optical science and technology he'd earned in China. But after a semester of struggling to find a research group that meshed with his areas of interest, he realized his problem: what he wanted was hands-on experience.
He found that experience in the Data Storage Systems Center.
"At the time, Jimmy Zhu was listed as a professor who was taking physics students," said Zhou, now a member of the technical staff at Headway Technologies. "I went into his group and found it quite interesting."
Zhou's project, determining the noise of magnetic heads, required a strong engineering background. He opted to transfer into the electrical and computer engineering department, where he'd have more time to work on topics that really interested him — like magnetics — while developing the skills he'd need to be successful on his project.
And what a project it was. While working on his master's degree, Zhou investigated thermally excited magnetic noise (noise in magnetoresistive sensors caused by thermal agitation of magnetic spins), a phenomenon that was new but not well understood prior to the research Zhou performed in Zhu's group. In fact, the work done in Zhu's group was some of the first to actually observe experimental evidence of the origin of the noise ( i.e., the thermally excited ferromagnetic resonance), and the testing method the group used has been widely adopted by the hard drive industry in read head testing.
"I think the knowledge we gained in the study has provided a lot of insight for understanding this new breed of noise." Zhou said. "This kind of noise is one of the worst kinds you can have in today's read heads. Five years ago, it was not too important. Now, it's the most important noise."
After he earned his master's degree, Zhou switched gears and focused on contact recording. He built a contact recording system while working on his PhD that he said offered the best performance of the few systems of its kind in existence.
"We built one contact recording system that has given the best performance of all the systems that have been built or have been reported," he said. "As far as I know, there are probably less than 10 such systems, probably just five systems that existed in the U.S., and we built one."
Building the contact recording system allowed Zhou to investigate a recording head's remnant behavior — meaning that the magnetic field remains and recording continues after the current is shut off. "I think the results we showed have never been shown before," Zhou said. "Because of that, we attracted industry interest in this area," including funding from DSSC sponsors like Seagate, Headway, TDK and Western Digital.
In his role at Headway, Zhou is continuing his commitment to hands-on, experimental work. His research team is developing an advanced concept of magnetic recording and magnetic read heads for future generations of magnetic recording technologies for hard drives. In just a few years with Headway, Zhou has developed simulations that are producing quality results and impacting the industry.
Zhou attributes much of his professional success to the education he received at the DSSC. "
"The key capability I learned — I think any PhD student learned while attending graduate school, especially at Carnegie Mellon — is that you're not really learning specific techniques," Zhou said. "What you learn is the greater ability to learn new things. In other words, whenever you encounter some new problems or step into new areas outside your own background, you know how to approach it, how to get yourself familiar and become an expert in it. I think that's one thing that is really beneficial from graduate work, from the graduate life, and it's the most valuable experience I have."
In the coming decades, Zhou hopes to be able to use that experience to break new ground in the use of magnetics. He's most interested in discovering new phenomena and leveraging existing technology to make new products. Magnetics, he says, can be used in more areas than data storage — areas like biology, where researchers are trying to use magnetic technology to study various diseases at the molecular and cellular level. "If we combine the techniques and the knowledge of different areas, we may be able to produce something very good for society," Zhou said.
All of this stems from his training in the DSSC.
"After graduating from the DSSC, I feel like there's nothing that I cannot do. Anything I will be given, I will be able to do it and do it perfectly. And I will have my own insight, my own input, from the technique of learning that I obtained at Carnegie Mellon."