Franken remembered — by Alan Hill

How did it come about that Peter selected me to perform the original optical harmonics experiment? I was only a sophomore at the University of Michigan, taking a first-level physics course at the University of Michigan. After class, I asked Professor Franken what he would expect to happen if I applied an intense pulsed magnetic field to an aluminum cylinder by magnetic induction. He said…”I suspect it would be crunched short and fat”. My answer was…”No, it is crunched long and skinny”, whereupon I pulled out a cylinder I had so crunched in my home lab as a high school student. Peter then said: “I have a project for you to do this summer!”

He provided me with the first commercial (Trion Instruments) ruby laser, which put out 3 joules in 2 milliseconds (Q-switching had not been achieved yet). Realizing that harmonic production would scale quadratically with power, I intentionally pushed the flash lamps to their explosion point, thus managing to produce an initially invisible spot on a glass spectroscopic plate. I tossed the first plate into the trash, but then realized that a closer examination under the microscope might reveal something. It did. The one piece of evidence for optical harmonics (a visible speck on a spectroscopic plate), sent as a figure with our paper into Physical Review Letters, was removed by the journal’s lay-out person who had assumed it to have been left by a fly.
Here are a few of Peter Franken’s characteristics:

• Peter loved to shock or startle people; he was always full of mischief!

• Peter liked to play the “devil’s advocate” whenever possible. He would question the viability of a new proposal or concept, and could usually debunk them with a mental calculation if they were not sound; and he would often challenge the victim with a nickel bet (payable only in check- to be framed on his wall). He often lost, since he challenged everything – but sometimes he won.

• Peter never took himself too seriously, and he had the nerve to try anything. He was fond of saying: “It is easier to be forgiven than to get permission”, or “I’m going to get kicked in the ass for this, but my ass is big enough to take it.”

• When Peter felt someone had been seriously wronged, he has been known to make it a long-term commitment to defend that person, or to help them in every way possible. Examples: Gordon Gould with his laser patent; Walter Spawr with his trial defense and ongoing vindication.

• Peter had a very broad-based imagination and creativity in physics, but also viewed administrative problem-solving as nearly as interesting. • Peter felt genuine concern and affection for many – an aspect which transcended even his formidable talent for doing physics.

       Alan Hill, 2011