Lixin Dong
Professor
City University of Hong Kong
Hong Kong, China
Education:
- Ph.D., Micro Systems Engineering, Nagoya University
- M.S., Mechanical Engineering, Xi’an University of Technology
- B.S., Mechanical Engineering, Xi’an University of Technology
Work Focus:
Dong focuses on nanorobotics, and works in the Department of Biomedical Engineering. He has offered graduate level courses in nanorobotics, nanofabrication, and nanosystems; teaching the building blocks, fabrication, assembly, and characterization of some nanodevices and systems, such as electromechanical systems, photonic systems, and fluidic systems.
Advice to Students:
“Volunteer at a research lab to get a feel of the field.”
Links:
– City University of Hong Kong Advanced Micro-/NanoRobotic Systems Lab
Interview:
Q: In which Nanotechnology technical fields does your work apply best?
Dong:
- Nanoelectronics
- Nanosensors and Nanoactuators
- Nano-Metrology and Characterization
- Modeling and Simulation
- Nanofabrication
- Nano-Optics, Nano-Photonics, and Nano-Optoelectronics
- Nanomagnetics
- Nano Energy, Environment and Safety
- Nanorobotics and Nanomanufacturing
- Nano-Biomedicine
Q: When did you first find that your career path focused on nanotechnology?
Dong: In the end of 1999, when I went to Japan for my Ph.D. studies, I was originally working with large scale robots to do machining….before that I had been working on machine tools focusing on precision machining. It was at this time that I transferred my work to the nanometer scale. I’m so interested in robotics — and the idea of working with robotics at a small scale is perfect to me.
Q: What current nanotechnology applications are you working on?
Dong: Nanorobotics is my main focus. And actually, nanorobotics has two major groups, one is medical focused, such as “swallowable doctors,” where you have nano-sized robots to do surgeries inside the human body, or just do some diagnostics. The other major group is manipulation for manufacturing, actually. This was proposed by Richard Feynman — but he didn’t give the details, the technical details, but he did say that physics doesn’t say no to such things. Then Eric Drexler proposed something like an engine of creation, that is, a machine for assembling molecules. So you can use nanomanipulation to make molecules, using a mechanical method, very different from the traditional chemical method. I am very interested in both of these groups. Actually, I have been working on manipulation for years — starting with manipulation inside the scanning electron microscope, and then the transmission electron microscoperoups, one is medical focused, such as “swallowable doctors,” where you have nano-sized robots to do surgeries inside the human body, or just do some diagnostics. The other major group is manipulation for manufacturing, actually. This was proposed by Richard Feynman — but he didn’t give the details, the technical details, but he did say that physics doesn’t say no to such things. Then Eric Drexler proposed something like an engine of creation, that is, a machine for assembling molecules. So you can use nanomanipulation to make molecules, using a mechanical method, very different from the traditional chemical method. I am very interested in both of these groups. Actually, I have been working on manipulation for years — starting with manipulation inside the scanning electron microscope, and then the transmission electron microscope.
Q: What’s the most rewarding thing about working with nanotechnology?
Dong: Nanotechnology is a really exciting field…and a broad field, so you can learn a lot of new things. I think both robotics and nanotechnology involve a lot of interesting subfields as well. For instance, nanotechnology involves nanophysics, nanochemistry, nanomaterials, nanoelectronics, and photonics. And also I’ve always been interested in robotics. With robotics, we want to make something like ourselves, and of course this also involves everything. The field of nanotechnology is simply a very interesting field — and one that requires strong creativity. You can do what you are thinking, dreaming, or imagining. So it’s really fun, and everything is exciting. Anything you create might be the first one ever created in the world! You can make the impossible into the possible.
Q: Is there an example you can provide that shows how something you’ve worked on has positively impacted the world?
Dong: Oh yes….I have been collaborating with others at ETH Zurich on something called “swimming robots.” We call that “artificial bacteria flagella.” That is a coil, and actually we can use an external rotating magnetic field, to make the robot rotate and to make it “swim.” That said, I think the potential impact could be very big, because, that could be the first prototype for the “swallowable doctor.” It’s still very primitive and in a preliminary stage, but I think the potential impact is high. It’s exciting to work in this area because we are all still discovering new nanomaterials and structures, which will change what we can do. Another example is characterization, where we can understand the different properties of nanomaterials or nanostructures in a single structure. I think the impact of working in nanotechnology is very fundamental, but important. And we provide some experimental tools for people like materials scientists, physicists, chemists, and others that will change the systems, products, and solutions of the future.
Q: In which areas do you anticipate future commercialization of nanotechnology having the greatest positive impact on the world?
Dong: While the future commercialization of nanotechnology will involve many fields, I would pick up post-silicon nanoelectronics such as carbon-based chips and quantum devices, where nanorobotic manipulation may play a significant role in fabrication, assembly, and characterization. Bottom-up fashion may take over the conventional lithography-based processes. Another one seeming equally great is the emerging nanorobotic medicine featured by targeted drug delivery, local diagnosis, sampling, and in-body therapy.
Q: What do you think is the single greatest impact nanotechnology has had on the world thus far?
Dong: The first usable nanotechnology actually was the AFM cantilever with a nanotube tip, I think. That was commercialized at the beginning of 2000. You know some people like Meyya Meyyapan’s group still all collaborate on it. They opened a spin-off to assemble nanotubes and a combination of AFM cantilevers to make a very sharp and very tough AFM cantilever tip. And I think that the use of Scanning Probe Microscopes (SPM) is very successful, as an example of nanotechnology. Dip-pen nanolithography based on an AFM was commercially very successful. My own group is initiating a nanotube fountain pen to directly “write” 3D metallic nanostructures—I’ll give a talk on this tomorrow at this IEEE-NANO conference. The nano fountain pen can also use an AFM as a “writer”.
Q: Over the past decade, nanotechnology has moved out of the lab and is making a real impact in society. Have you worked on any efforts that helped to commercialize nanotechnology and resulted in new products or processes?
Dong: I have been working on a 3D printer for metallic nanostructures based on the nanotube fountain pen we developed more than ten years ago, and a non-invasive nanorobotic surgery system based on the swimming nanorobots with the aim of commercialization. However, both are somewhat mid- or long-term projects and no products are available yet.
Q: Did your university training help you in your nanotechnology work?
Dong: I think so. But you have to stay involved….there are many conferences, and it is important to connect. Nano is not so special actually, in the scientific aspects, but is more important in the technology and the engineering aspects. That’s why Richard Feynman said that we may not have new physics here, but we will have a completely new way to change the world. He said that “we could arrange atoms one by one, just as we want them,” to assemble a new world.
Q: Do you have a mentor? Did you in your college years?
Dong: Yes I think so, guidance counselors provided some assistance, but I think my ideas have been inspired mostly by collaboration. For example, we created a very simple structure, a sphere on a nanotube. But, we never thought this was something useful. But a friend of mine, once when he saw it said, “well if you have a pair of this, you can make an optical enhancer!” If you use two of these nanostructures, and put them very close together, you can use the surface plasma resonance to make an antenna that can work with the resonance of light. This is actually a very interesting structure, and it has very important applications, for instance we can use this optical antenna to improve the absorption of the solar energy of solar cells. You will have better solar cells.
Q: If you had to do it all over again, would you still focus on nanotechnology applications?
Dong: I think this is my life career, because the dreams of the future are very exciting. Working at the nanoscale, you can make just about everything that is thermodynamically stable. You can assemble anything that you can design. And I am inspired by nanotechnology applications — I think that nanorobotic medicine is a very important example — even if you make conservative progress in this field. For example, some of my collaborators are working on surgeries inside the eyes. In the eye, you can see your robots, so it’s relatively easy. That’s very interesting. And the next step is medicine through the blood vessel. You can send some drugs with a robot to deliver it to targeted cells, such as cancer cells. Then, consider manufacturing with nanotechnology — so you can make a new cell, for example, after you kill a bad one. You find a cell that is getting old, you can make a young one. A lot of things will be changed. So I think nanotechnology is definitely a worthy focus for a life. I intend to continue to struggle with the challenges of nanotechnology because the future is what we dream.
Q: What advice do you have for pre-university students?
Dong: I’m encouraging my university students that nanotechnology can help them turn dreams into reality — and that’s really amazing. Pre-university students can start learning now by working with models –they could make models of molecules, and learn from some micrographs, some websites, and some scientific fiction — actually some examples in scientific fiction are now becoming reality.
