Seeing the Unthinkable: using electrical fields to levitate particles
Blog written by the project team
Seeing the Unthinkable: Steven Claydon interviewed by Nur - read more about Nur who joined the project in summer 2021 as a King’s Undergraduate Research Fellow (KURF) further down the blog
At the end of her KURF project, Nur interviewed Steven Claydon about his background and motivations for the project. Here is her summary of that conversation.
1. Both Steven and I agreed that it was the melting of two fields together – Art and Science – that attracted us to this project.
2. For me, the project was a good way to gain some experience in research and brush up my scientific public engagement skills. After completing the Malaysian play in 2020, this project seemed more delightful than a purely scientific project.
3. After completing his degree, Steven spent two years working at the Natural History Museum in London before starting his MA. While he was training as a guide that explains to visitors the collaboration between different departments at the museum and how it would affect the exhibitions on display, Steven had somewhat an epiphany that would eventually inspire and influence his career. Among many other things, he is mainly interested in the relationship between materials in nature and their cultural significance as well as utility. His interest in this relation has led him to be involved in crossover projects between art and science, as science too, studies natural phenomena and material.
4. A particular concept that is of particular fascination is the idea that something becomes more visible the more we conceal it. This first became known to Steven at the Natural History Museum, when he got to know that gold-plating an object allows for better inspection under a scanning electron microscope. This concept can be seen across many of his works – art pieces featuring electroplated items such as a telephone and a lens.
5. Furthermore, Steven is interested in the reciprocal possibility of this relationship. He believes that the artist never has full control, and that somehow, the subject of inspection is also inspecting us in return.
6. This two-way relationship is seen across both the arts and sciences. An artwork or experiment that is used to depict and study nature, in turn challenges the artist or scientist as well as the audience, their existing personal narratives and perception of the world. They tell us more about ourselves and the world.
7. Thus, befitting with this project, which is a bridge of the two fields, Steven proposes these as our central themes:
a. The idea of revealing by concealing
b. An interaction between the inspector and the subject of inspection
c. A cultural significance and natural utility of the material that enlightens the inspector – culturally and/or fundamentally
8. Taking inspiration from 2001: A Space Odyssey as well as the real-life rapid development of AI, Steven proposes the construction of the ion trap replicating Hal’s eye. By considering the current experimental setup of the trap, we thought of the ways in which this can be achieved:
a. The rim of the trapping region in the metal plate would make up the boundary of this eye
b. Lenses can be put on either side of the boundary, so as to magnify its content
c. The particles are placed within the space unclosed by the lenses
d. A voltage is connected to the boundary, producing the electric potential that traps the particles
Therefore, the inspectors get to observe the particles that get trapped, and those that do not.
9. For the piece to be meaningful, it is important that the particles have some kind of cultural significance. Some materials suggested by Steven are:
a.Diamond dust (main choice – proven successful a day after this interview)
b. Lunar Regolith Simulant
c. Flour (what we used during the earlier tests in the lab)
10. As for aesthetics purposes, anything is on the table as long as we can figure out the reason behind them. As for now, what’s certain is:
a. Steven would like to incorporate the complementary pairing of green and pink (LED light and the slightly damaged spare Thor Labs camera)
b. Flour aesthetics
c. Steven is also open to getting inspiration from others’ works
Seeing the Unthinkable: Successful Prototype
By the end of the summer, we had a working prototype for Seeing the Unthinkable. A 1cm diameter aperture was made into a plate of aluminium, which itself was connected to an oscillating high voltage. This allowed charged particles to be introduced into the aperture. We used diamond dust, forced through a charged needle in a process called “Electrospray Ionization”. In this image, you can see a diamond particle as a tiny green dot, levitated at the centre of the experiment.
Seeing the Unthinkable: King’s Undergraduate Research Fellow
This project was lucky to have Nur Imanina join us as a King’s Undergraduate Research Fellow (KURF), building our prototype levitation system. She wrote this short blog about joining the project:
My name is Nur Imanina and I am a Malaysian student who had just completed a BSc in Physics with Astrophysics and Cosmology at King’s College London. This summer, I am working on a project with King’s Levitated Nanophysics Group led by Dr James Millen and in collaboration with local artist Steven Claydon under the King’s Undergraduate Research Fellowship (KURF) programme.
While applying for KURF, I chose James’ project because:
1. Out of all the projects on the list, his stood out – rather than a purely physical or mathematical project, his was a collaboration between the Sciences and the Arts.
2. I found the bridge fascinating as on top of constructing an ion trap, I would have the chance of giving creative input.
3. The main objective of the project was to produce an exhibition piece out of the ion trap, for a King’s festival. I found it exciting to participate in a project of such level of significance to the university.
4. I was keen to work with James as he is a very good lecturer and science communicator (I was convinced by the 2019 Cumberland Lodge weekend seminar and his second-semester lectures on Quantum Mechanics).
5. I was also interested in the public engagement element of the project – I wanted to improve my scientific communication skills.
The King’s Undergraduate Research Fellowship programme: a brief description of KURF along as well as how I applied for this project with James.
The New Normal: a recount of the expectations and safety measures taken by King’s in light of covid-19 during the fellowship.
In Seeing the Unthinkable we will explore the ability of the human mind to interpret information, such as sounds or data, via an unusual visual medium: the motion of tiny particles levitated by electrical fields. We choose this unusual medium since it reflects the research of James Millen, but how on earth can we use electrical fields to levitate things!?
If you apply a voltage to something conducting, like a metal, then an electrical field will be generated around it. This field can exert a force on charged objects, allowing you to pull or push them around. You could imagine that you could use electrical fields to “push” on an object from all sides, causing it to levitate in space. Unfortunately this is not possible due to Gauss’ Law, which says that you cannot make an electric field that is stable in three-dimensions; think about how you can’t balance one magnet on top of another, it’s not stable.
However Wolfgang Paul realised that you could pull a trick on nature by rotating the electrical field rapidly, so that the unstable charged object is being constantly caught by the moving electrical field… this is hard to explain in words, but intuitive if you see a picture, or even better a video! This technique goes by many names: the Paul trap, ion trap, RF trap, Quadrupole trap…, but whatever it’s called, it earned Paul the Nobel Prize in 1989, since this technology has allowed us to explore the fundamental nature of individual atoms, and sits at the heart of quantum computers.
There are many different geometries of electrical traps, depending on application. a) a trap from James Millen’s group, optimized for detecting the motion of the trapped particles, b) a “Kingdon trap” used to measuring the mass of charged molecules (Mkotl – Wikipedia: Ion_trap), c) The Pine ion trap for quantum computing (Alpine Quantum Technologies).
A “rotating electric field” may sound very complicated, but really all it means is that you need to use an AC voltage (like that which comes out of a plug socket) rather than a DC voltage (like that which comes out of a battery). There are many options for the geometry that you use to make an electrical trap, but we wanted to design something this makes it as easy as possible to see the levitating particles. Here are some images that we will leave without too much explanation, illustrating our thought process at this ideas-development stage.
Some concepts for our trapping geometry, optimized for human observation, inspired by the work of Christian Schmiegelow (Universidad de Buenos Aires). A simple aperture will be used to confine the particles in a “pancake” shape, with additional electrodes to control their motion.
Some rough computer modelling of the trapping region. We can see that the electric field is confined within the aperture of the trapping apparatus.