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Nanotechnology: Toward matter programmable to atomic precision

In the Edigest email from Nanotechnology.com, we found the interview below with a young researcher whose work has been mentioned here before. Normally we don’t reprint items in their entirety, but I could not find this on the Nanotechnology.com website, or elsewhere on the web, so here it is. Its appearance in the Edigest was sponsored by PurpleGoldMedia. Note that the researcher regards the so-called “fat fingers” argument to be incorrect:

Alexander Wissner-Gross is engaged in nanotechnology research that will improve far more than just computation

Interview with Alexander Wissner Gross
Questions by Sander Olson. Answers by Alexander Wissner Gross

Alexander Wissner-Gross is a Harvard doctoral candidate who is currently researching several aspects of nanotechnology. He has recently authored a paper on reconfigurable nanowire interconnects. He holds several nanotechnology-related patents, and has won numerous awards and distinctions for his research. He plans on commercializing his research after receiving his doctorate.

Tell us about yourself. What is your background, and on what projects are you currently working?

I am a scientist. (www.alexwg.org) I graduated from MIT in 2003 with triple bachelors in Physics, Electrical Engineering, and Mathematics. I feel fortunate to have been the last person MIT allowed to triple major, as it afforded me both breadth and depth. While an undergraduate, I also tried to achieve this goal by spending at least a semester or summer doing research in every department. After MIT, I received a Hertz Fellowship and decided to approach science from the perspective of a physicist. I went to Harvard, where I received a masters in Physics from Harvard in 2004. I am currently a doctoral candidate there. My broad interests, yet focused training, have impacted the papers that I’ve written and published. Topics range from mobile personalized education to reconfigurable nanowire interconnects, all with the common theme of making our physical and biological worlds more programmable. I even wrote and directed a film, “Song of Diamond and Ice,” and am now a Finalist in the 2006 Materials Research Film Festival.

You are also a successful inventor, a teacher, and an entrepreneur. Describe you’re accomplishments in those fields.

I am actively involved in inventing, teaching, and entrepreneurship. I hold 3 patents (www.alexwg.org/patents.html) and am an Inductee into the National Gallery for America’s Young Inventors. I have written (www.alexwg.org/distinctions.html) physical simulation software, and was the first place individual in the USA Computer Olympiad in 1998. I was awarded Harvard’s Book Prize and Certificate of Distinction for excellence in undergraduate education. Furthermore, I developed for my students a novel system (www.alexwg.org/ICALT2006.pdf) for automatically preparing reading lists.

More information about me can be found at: www.alexwg.org

Your Harvard dissertation is on “matter programmable to atomic precision.” What does that mean? What developments could result from such capabilities?

I view nanotechnology in the larger context of making our world physically programmable. Ultimately, this means that making individual atoms act and move exactly the way we like should be as simple as writing a computer program. As the physical world becomes more programmable, many problems of daily life, from fixing broken computer parts to keeping medical implants from corroding, should become more tractable.

In my dissertation, I attack from a variety of angles the challenge of making matter programmable. With colleagues, I produced the world’s first “molecular graph paper” of gold dots that have controllable spacings with a sub-nanometer accuracy. Our graph paper might serve as a sort of breadboard for prototyping electronic nanosystems. With colleagues, I synthesized the world’s first single-crystal silicon nanotubes, nanocones, and nanotube networks, which have the capability of electrically pumping attoliters of material. Silicon nanotubes may be an ideal material for syringes in nanomedicine since their internal diameter may be tuned to be as small as the diameter of single-stranded DNA. In recent experiments, I showed that the dielectrophoretic effect could be used to position, test, and assemble nanoelectronic devices into larger circuits. Such dielectrophoretic manipulation undermines the “fat fingers” argument against atomically precise nanosystems since field enhancement allows force field precision smaller than an electrode tip. In a computational study, I predict that certain diamond surfaces can locally raise the melting temperature of ice above human body temperature. Such surfaces may be useful in resolving the defrosting problem of cryonics, since they may enable atomically precise manipulation, in vivo, of biomolecules using “tweezers” of high-temperature ice. Finally, I have conducted the first theoretical analysis of an entire class of self-assembly interactions with implications for engineering macroscale behaviors by tuning local microscale interactions.

You recently wrote a paper on nanowire interconnects. What advantages do these nanowires have over conventional interconnects? Could these nanowires be used for purposes other than computer interconnects?

The advantage of the nanowires I used is that they are freestanding, so that they may be reconfigured. A number of novel applications for reconfigurable nanowires can be imagined, which conventional interconnects cannot address since they are physically immobilized. For example, reconfigurable nanowires might enable breadboards for the rapid prototyping of nanodevice circuits, or brain-like networks of nanostructure-based artificial synapses, or fault-tolerant logic in which broken components are replaced automatically from a liquid reservoir.

How easily could nanowires be incorporated into existing semiconductor fabs? When do you anticipate nanowire technology being used in commercial products?

The answer depends on the definition of ‘nanowire.’ In a sense, the metal interconnects produced in fabs today have been commercialized ‘nanowires’ for years, albeit fully bonded to their surrounding material. In contrast, my research used freestanding nanowires because it was essential for the wires to move. In the space between freestanding and fully bonded nanowires, I think there are immediate commercialization opportunities for incorporating nanostructures into existing materials (e.g., surface emission displays).

Several nanotech startup corporations are claiming that they can develop molecular electronics systems within the next decade. Would you recommend that anyone consider investing in such startups?

If I wanted to make a profit by investing, I would at least wait a few years until I felt that nanotech startups had a clear commercial advantage over existing solutions. In a classic case of technology-driven versus market-driven entrepreneurship, it is not clear how some of the more visible startups are solving a consumer or business problem better than other, more established players.

Do you plan to form any nanotech startup corporations based on your nanowire research?

Yes. After I complete my doctorate, I hope to be a professor and an entrepreneur.

What corporations and institutions are funding your research?

The fantastically generous Fannie and John Hertz Foundation had paid for my graduate education and research. The Hertz foundation is a not-for-profit organization that provides fellowships to students engaged in doctoral research in the physical sciences.

More information on the Hertz foundation can be found at:
(http://www.hertzfoundation.org/dx/Foundation/)

You have two patents on robotic manipulation systems. How are these patents related to your nanotechnology research?

My first two patents (US #6,216,631 and #6,335,059) dealt with methods for controlling a certain type of fluid surface such that the surface is capable of manipulating objects. In general, my view was that approaches for nanomanipulation using fluids (e.g., gravity waves or electrophoresis) rather than solids (e.g., scanning probe tips) had received comparatively less research attention. The patents were the basis for a nanotechnology business plan, “Granular Ink,” which won the MIT $1K Business Idea Competition in the Tiny Technologies category.

More information on “Granular Ink” can be found at:

http://www.harbus.org/media/storage/paper343/news/2003/04/28/News/Hbs-Team.Selected.As.A.Finalist.In.The.Nations.Largest.StartUp.Competition.For.U-428646.shtml?norewrite200701101259&sourcedomain=www.harbus.org

Aside from your own research, what aspect of small technology excites you the most?

I am most excited about nascent bridges between nanotechnology and nominally unrelated fields, such as artificial intelligence, botany, and economics. For example, what are the economic implications when bits become separated from atoms through programmable tiny technologies?

How do you see your research evolving during the next decade?

We are approaching a unique time in the history of nanotechnology research. Traditionally, much academic research into freestanding nanostructures (e.g., nanotubes and nanowires) has been motivated by a desire to extend Moore’s Law down to nanometer length scales. Yet, nanometer length scales are now being plumbed for the first time for mass-produced memory and logic without using these structures. What I would like to do over the next decade is to explore how atomically precise programmable matter can be used to directly and positively impact everyday life, beyond just improving computation.

One Response to “Nanotechnology: Toward matter programmable to atomic precision”

  1. Phillip Huggan Says:

    Diverse research interests.
    The fat-fingers problem refers to the minimum curvature of an SPM tip surface when depositing a reactive moiety many times smaller than its diameter. Using a solution as the fingers is cheating, in that the product repetoire won’t be atomically precise (not necessary for computers).
    I wonder if the researcher is considering anologous techniques to join CNTs?
    The ice on diamond seems interesting; should be related to diamond surface wear and stiction.
    I’d be curious to know what kind of instruments are used for nanomanipulation using fluids, that don’t overlap with those using SPM-tip based actuation.

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