Follow-up on molecular electronics

Exercise #5 discussed a 1983 paper by Forrest Carter on proposed fabrication techniques for “molecular electronics”—electronic devices made from molecular building blocks, which held or hold promise for extending Moore’s Law beyond the limits of silicon. One question was “How many of these methods do you think are in use today, almost 35 years later?” I don’t want to imply that there’s necessarily a moral lesson to be drawn from the answers to the exercise; it was open-ended for a reason. With that in mind, to my knowledge, only one—nanopatterning with LB films—has become an active area of study in a form somewhat like the proposal, although other methods for accomplishing similar goals are also now subjects of experimental research.

For context on Carter, I’ll repost a comment I made on tumblr:

Luke Muehlhauser’s descriptions for OPP of cryonics and especially of molecular nanotechnology as case studies in failures for early field-building strike me as a little odd coming from someone who put Instrumental Community in his annotated bibliography. At the very least why not say something about the success of field-building in (not-MNT) nanotechnology?

This reminds me that I wanted to share “The Long History of Molecular Electronics”, an article about a sort of ancestor of MNT, by Hyungsub Choi and Cyrus Mody (IC author). (A lot of this also shows up in Mody’s new book The Long Arm of Moore’s Law: Microelectronics and American Science, which is really excellent and kind of about me personally.)

Before Drexler, there was Forrest Carter. At the beginning of the story, Carter is a chemist at the Naval Research Lab, specializing in x-ray photoelectron spectroscopy, and he gradually shifts to community-building:

Critically, Carter’s interest in molecular computing grew out of an institutional and disciplinary environment similar to [IBM chemist Ari] Aviram’s, as well as a personal curiosity dating to his graduate training at Caltech. There, he had studied organometallic chemistry under Howard Lucas, graduating in 1956 (Carter, 1956). His Caltech mentors also included Linus Pauling and Richard Feynman; indeed, by Carter’s account, he attended parties at Feynman’s house and played bongos and talked science with the older man. It is interesting to note that Carter knew of and was influenced by Feynman’s (1960) famous ‘Room at the Bottom’ speech – much more so than most other early nanotechnologists.

Moreover, Carter incorporated elements of the Feynman persona into his own presentation of self, developing an expansive, charismatic style that helped him promote bold visions and gather protégés, but which also led to institutional conflict. Like Feynman, he had a taste for exotic hobbies (hot rods, motorcycles, fencing, platform diving, salsa dancing); and, like Feynman, he became known for extraordinary parties, risqué banter, and a coterie of young acolytes. Carter’s striking appearance, rumbling voice, and colorful banter (cited to this day by skeptics and believers alike) personalized molecular electronics as neither Aviram nor the Westinghouse engineers had before him.

By 1983, the radical turn in Carter’s vision for molecular computing was visible in his community-building strategies as well. That year he held the second of his Molecular Electronic Devices workshops (Carter, 1987). Where the first conference had been attended mostly by conducting polymer researchers (many of whom were funded by the Navy), by the second workshop those people were replaced by an eclectic mix of synthetic chemists, biochemists, lithography specialists, and provocative speculators such as Eric Drexler. This broadening of topics and personnel is indicative of Carter’s unmooring of molecular electronics from a particular material such as polysulfur nitride or TCNQ, and his construction of a big tent for all things ‘molecular’.

For Carter, it was among the visionaries in that tent – people like Drexler, Stuart Hameroff, and Stephen Wolfram – that he could discuss cellular automata, molecular assemblers, and biological computing and obtain material for the more radical parts of his vision.[47] That vision was quickly attracting widespread attention. Carter was publishing more papers in mainstream physics and surface science journals in the mid 1980s than at any time in his career; but he was also publishing in more off-beat edited volumes that some of his peers and supervisors were beginning to contest.[48]

Thus, Carter fell into that familiar category of scientist for whom his peers’ evaluations of his science was inseparable from their interpretations of his character and mental state.[51] To his critics, Forrest Carter avoided producing experimental results because he was a second-rate chemist; to his supporters, he was a community-builder whose work was more important for national security than the research the Navy demanded. To critics, he was a wild speculator whose misunderstandings of quantum chemistry would bring the Navy into disrepute; to supporters, a charismatic genius who deliberately advanced unfashionable ideas to provoke discussion .

In some ways he gives us an archetype halfway between Drexler and the mainstream. He was from the start a member of the research community—an experimentalist, even, if not when it came to molecular electronics. He brought the “field” (as much as it was one) into some disrepute (moreso in the US than elsewhere), and his big tent mostly collapsed after his death. But a kernel of experimentalists—who may not have talked to each other without Carter’s efforts—regrouped and began to produce credible results (in the least speculative part of the ME research program) with the help of new technologies like scanning probe microscopes. That new generation of molecular electronics has grown into a relatively mature interdisciplinary field. And note that the speculation that set all this off is still controversial—plenty of people expect we’ll never be able or want to manufacture a “molecular computer” even in the reduced sense of “integrating single molecules with silicon”, and no one thinks we’ll be there soon—but since the field doesn’t live so much off of hype, researchers have space to say “hey, it’s basic research” and carry on.

As an addendum to the repost, I should also quote footnote [47]:

According to Hank Wohltjen, Carter and Drexler had a sustained correspondence but eventually they ‘parted ways in that Forrest was not seeking limelight for this stuff, he was trying to play it down and focus on more doable things. And Eric was more into sensationalism’.

And note that the paper linked in the exercise is one of his “papers in mainstream physics and surface science journals in the mid 1980s”, not in an “off-beat” volume.

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