A story of a scientist

My first laser

By Physics Today on August 12, 2010 1:58 PM | 1 Comment | No TrackBacks

When Theodore Maiman introduced the ruby laser on 16 May 1960, with pulses of bright, coherent red light from his laboratory at Hughes Research, I was an 11-year-old "Sputnik" kid playing dangerously with homemade rockets and radio circuits.

Although I was too young to pay much notice then, I got hooked on lasers two years later when I read an article in Popular Science magazine titled "The Incredible Ruby Ray" (scroll to page 89). It thoroughly captivated me—I just had to make a laser for myself!

The trouble with such a venture for a 13-year-old boy was the required equipment; a cigarette-sized ruby crystal and a high-energy flashtube far exceeded my discretionary funds. Cash from delivering papers and mowing lawns could keep a junior scientist stocked with chemicals and radio parts, but the components for a pulsed ruby laser would require a major bequest from a rich relative. I didn't have one.

After I had read the article in Popular Science, I started reading any article I could find on lasers and spending afternoons and weekends in the library of Philadelphia's Franklin Institute. I needed to find someone who would lend me the required ruby crystal. By 1963 a small number of companies in the United States were making those precisely grown crystals, but the price for the required two-inch-long specimen was well over $1000.

I wrote letters to every such company that I could identify, explained my plans, and inquired whether I could borrow a ruby crystal. To my delight, a research team at RCA's engineering research facility in Camden, NJ, wrote back and invited me for a visit. I took that to mean that they wanted to check me out before offering to help.

I left the RCA laboratory with not one but two laser crystals, in addition to lots of advice on how to build my first laser. The engineers I met during my first visit to RCA stayed in touch with me during what became my four-year venture as my lasers became increasingly sophisticated (and better working) and my ability to ask better questions matured.

My third laser, completed in 1965 (shown in the photo), was a reasonable scientific tool for the time. Making good use of a scientific tool for discovery is an important component of a scientist's education. While pondering what to do with my laser, another venture in letter writing served me well. I wrote to Hermann Muller, a professor emeritus at Indiana University who had won the 1946 Nobel Prize for Physiology or Medicine by showing that exposure to sufficient quantities of x rays causes damage to biological cells and eventually leads to mutations.

I asked Muller to speculate on whether the unique characteristics of laser light—spectral purity and ability to tightly focus—might have novel effects on biological systems. To this day I marvel at the three-page response he sent back to me, a 15-year-old high-school freshman at the time. Muller's letter included ruminations on my query, suggestions for my experiments, background tutorials, and a long list of suggested reading.

His recommendations led me to do a series of experiments with my model 3 laser that involved controlled exposures of frog eggs harvested from the backyard pond and onion roots dug up from the garden. My experiments won me some minor awards in the regional science fair in Philadelphia, but, more importantly, the experience taught me how to do experiments.

Ten years later with a freshly minted PhD in physics, and ever since, I have tried to be generous with my time whenever a young student sends me an inquiry or asks me for advice or for a loan of scientific gadgetry. I remember how the RCA engineers and Professor Muller took interest in me and how they influenced my career in a positive way.

Within every scientist is the drive to understand how things work and to discover new ways of doing things. Yet the fervor for discovery is cultivated by strong mentors who encourage, steer, and challenge the budding scientist until—and often long after—he or she becomes a professional scientist. My own fascination with science was fueled by the invention of the laser and guided by scientists who took a personal interest in my curiosity—mentors who had a tremendous impact on my life and career.

H. Frederick Dylla