Maker of resonators
Of the 34 accomplished violinists in UC Berkeley’s Symphony Orchestra, one has a day job for which he dons a Tyvek cap, coveralls and booties to fabricate MEMS resonators at the Marvell NanoLab in Sutardja Dai Hall.
Most days (and nights), you’ll find Ernest Ting-Ta Yen, a mechanical engineering Ph.D. student, immersed in the complexities of his MEMS (microelectromechanical systems) research. The aluminum nitride resonators he builds, aimed at new cell phones and communications applications, are designed to help shrink mobile devices while increasing functionality.
Happen upon him in his graduate student office at midnight, though, and you’ll hear lovely strains of music. Yen practices from midnight to 2 a.m., the only hours available to this busy researcher. He tries to practice every day, he explains, or he loses his technique. Add in twice-a-week orchestra rehearsals, occasional performances and time dedicated to his girlfriend, and this engineer is booked.
“There are so many times I want to give up [the violin],” he says. “But… I want to play.”
Last fall, Yen starred as a soloist, playing Erich Korngold’s violin concerto in the orchestra’s opening concerts in Hertz Hall. “He has a feel for the music,” says Katalin Voros, manager of the Berkeley NanoLab and a regular attendee of Yen’s performances. “He has the depth and temperament of a good musician.” To further his abilities, Yen studies under violinist Yukiko Kurakata as well as Alexander Barantschik, concertmaster of the San Francisco Symphony.
A native of Taiwan, Yen began playing at age 5. When he was younger, Yen recalls, he could practice five to six hours a day and often pushed himself to win competitions, eventually taking first in the violin category in the 2002 Taiwan National Music Competition. By high school, though, he decided against a professional career but continued to play.
When he came to Cal in 2006, Yen brought his violin with him, but he didn’t join the University Symphony Orchestra until the following year in order to focus on his engineering career. “I like to make things, so that’s why I enjoy MEMS,” he says. “Students fabricate their own devices here. And when my devices work and vibrate, it’s pretty cool.” Yen works in ME Professor Albert Pisano’s Berkeley Micromechanical Analysis and Design Group, and is also advised by MEMS expert Clark Nguyen, an EECS professor.
Resonators, which take the form of a ring or plate and vibrate at a defined frequency, are critical to a properly working cell phone. When someone calls you, millions of signals are flooding the air at any one point in time, and the phone requires a filter in order to pick up the correct signal at the correct frequency. By coupling several resonators together properly, Yen explains, they operate as a filter.
Yen’s acoustic wave resonators vibrate within the megahertz to gigahertz range, inaudible to the human ear. The biggest one, he says, is smaller than the width of a human hair. By building them so small, Yen and his fellow researchers hope to fit 100 to 1,000 of them, with different frequencies, onto a single die no bigger than 1x1cm2—an effort that will help shrink the size of portable devices without undermining their functionality.
In a strange twist of coincidence, the violin is also an acoustic wave resonator, vibrating in the 20- to 20,000-hertz range, Yen says. When he practices, he applies an engineer’s mentality to his left hand and fingers, which hold the violin and press the strings. It’s very mechanical, he explains, and control and precision are paramount.
The right hand, which holds the bow, is the opposite. “The expression of it determines the phrasing and the emotion of the piece. The bow arm is the soul of the music,” he says. “You use your bow arm to communicate with the audience and lead the orchestra.”
For now, Yen is concentrating on his dissertation while studying the Elgar Violin Concerto on the side. After he completes his doctorate this semester, he says, he hopes to remain in the U.S. and work in the semiconductor industry. He also hopes, one day, to earn a seat in a symphony. “In an orchestra, you play with 100 musicians. You communicate with each other by cue or eye contact, and the result is you make great music together. It’s magical.”
If you’re near campus, don’t miss the Department of Music’s free, weekly noon concerts in Hertz Hall.