31 October 2011

Electrons of time

It’s 5 pm on Halloween; dusk; the end of October, the eve of November and all hallows. These endings and beginnings seem only infinitesimally small marks on a continuum, rather than events with a real scope. The electrons of time. Comprehensible yet indescribable (and how apt that the last letters of that last word are so close to babble).

The donut is blown, ideas have been propagated, knowledge transferred, thoughts translated into other forms. And yet for me this process continues, with knowledge still distilling and being regurgitated in altered shapes. I continue to make things that are expressions of the time spent and information learned whilst I have woven the course of this process. Art. But this blog will end here. It is transmogrifying into another, a continuum of the work under another title. ‘Virtually resident’, the words that directly report my time as Leverhulme artist in residence at the University of Surrey, ends today. And do I have a final comment on which to close? I would caution my fellow makers against Residences that are geographically removed from their residences, it is a challenge. And what of silicon photonics? The process of science marches on. Today the population of the world purportedly reached seven billion; there is an ever increasing need for efficiency in our utilisation of resources; there is much for us to do to ease the existence of humanity. There is so much potential in seven billion people, so much that we have yet to do and discover. 

For me, part of my immediate future endeavour (my beatific vision?) is taking the form of words and images relating to science, silicon photonics, art, as a book, of which you can read more here. And so my final word here in conclusion (and which is, after all, merely the marking of a minutely transient moment)? I think it will simply be inconclusion.

12 October 2011

Blowing the dough (part 1)

I had wanted to write yesterday due to the binary beauty of the date, but the day was taken up with other Art matters, and the opportunity did not arise. More of that later, for now a report on the remarkably readily possible undertaking of the impossible.

A year ago I heard of a thing called a ring resonator. This object was at that time completely new to me, and my instantaneous, unstoppable response to hearing those words was an image of a luminous, diaphanous structure, floating in the nothingness of my mind. A glass circular form, indescribably light and fragile, imperceptibly pulsing with the energies of the universe, emitting an infinite range of coloured light from its integrally transparent curved clarity. A glass doughnut. 

And over the subsequent times that I have spent residing with the silicon photonics group this vitreous image has repeatedly reappeared, silently animate as it has been mulled in my mind. I had sought to make one, to have one made, but with no success, not least because of my stubborn demand that it must be blown rather than cast glass (to me there is a dynamism resulting from the trapped vitality of the former that is less evident in the latter). It was not possible. In a final effort to construct this wonder I set out on an impossible mission last week, blowing the last of the grant, and spent it at a glass studio on an exploration of the potential of the doughnut's formation, questioning the edges of its possible construction – is it really impossible?

And so it seems that the answer is no. It was made at first attempt through a combination of Kim’s expertise and a slightly brutish attacking of the glowing molten blob. True to say that the small leaden lump of chunky glass with rough edges that is the semblance of a glass doughnut does not exactly mirror the one in my mind, but technically it is exactly the thing I wish to construct. How easy (if a little diminutive) the impossible can sometimes be. The second go was neater but still small, and the third (again small) is as yet unseen by me as it had to be left in the annealing oven to prove when I departed. Now is the time to get excited about the fourth, which is to be constructed next week, and is to be as large as possible. Theoretically the limiting factor of this possibility is the size of the glory hole (the boxed blow torch that is used to reheat glass to enable continued working on it), so there is a technical finity to this thing that is somewhat more expansive in my head. But I am heartened that in the last week of my official time as artist in residence with the lab I have managed to construct the first thing that I envisaged. Things are looking up.

6 September 2011

What light breaks?

How did Romeo feel as he glimpsed the first shards of light that day as he stumbled into a consciousness of an outer world while encapsulated within Juliet’s? Today a lab meeting, in the boss’s office – up high amidst the wind and rain that is relentlessly affronting the building. A smallish contingent as a result of diverse slowing effects on other members of the group, but I take great pleasure from the interaction, varyingly business like and humorous. I am saddened at the thought that I only have one more month in this place; my time here is mostly gone.

The grey and gloom are pervasive in my mood as I walk around (and only enhanced by stumbling into Jeff Beck singing “Lilac wine” in a cafe as I stop to grab a coffee), and I feel as if my eyes are trying to absorb as much as possible of the quirky visuals that comprise the campus. The assorted travel trophies in the office; a folder entitled ‘Circles of light’; the oversized coffee mug; all the men wearing stripy shirts. These things bear a new weight in the wistfulness of the nostalgia of upcoming departure.

This residency has been a curious creature for me. I am always desolate at having to leave my home, to tear myself away from the peace and otherworldliness of my quiet and secret place. And I keenly feel the transitions into the weird, wider world – the crassness encapsulated in the free paper that has been discarded on my train seat, the towering spindles of teenage girls at the railway station last night, high on their platforms, legs topped by miniscule skirts, and the facile, protracted, fantasies of a Twilight movie that is playing as I arrive at my ever-welcome, ever-welcoming accommodation. And today the transition into this other world, that of the University; externally still slow and quiet, amid the rain, since term has not yet started. Yet behind the silent doors, along the quiet corridors the work beavers on. Here there is an ongoing wave of advancement; the group I am affiliated with are making tiny electronics devices that are at least as good as those made by the giant corporation of Intel; the five unassuming men I met with this morning are creating our future. It is extraordinary, what luxury to be here and share time with them; I am desolate at the thought of leaving again. I speak, yet I say nothing; what of that?

27 August 2011

aging of knowledge

Is there a difference between coming to know something that is known and coming to know something that was formerly unknown? Since all knowledge newly acquired is novel to the acquirer, is there a possibility of discriminating if the thing has previously been thought by others. (Or maybe stated in another way the question is can one detect creativity in oneself (let alone others)?)

What is understanding? Over and again I return to my attempts to envisage what an electron cloud is – why the doped semiconductor is more conductive than the undoped – I can regurgitate a sentence of the bookish teachings of the phenomenon, but I do not feel it. I do not have a sense of how the process actually works.

When I was first resident with Graham’s group I attended some of the lectures by Goran. His teaching leaves space within the lectures for the students to discuss amongst themselves, in order to problem solve and hence develop a deeper understanding of the subject. I was struck by the audio variations of the lectures – periods of low level sound as Goran spoke and showed slides, talked through examples etc, and then periods of vibrant noisy engagement as the students talked about the problem posed, among other less focussed chatterings. To me the energy contained in the audible discourses was the perceptible result of knowledge generation; tonal and volume variations resulting from the degree of insight; the sounds of the evolution of understanding. 

I used to find conversation (and argument) a useful tool for working through ideas, the discussion helping me to understand my view; the externalisation somehow clarifying the subtleties of complex notions. Nowadays I seem to find silent contemplation a more effective mechanism of generating understanding, with non-conscious thought arguably even better than mindful consideration for that purpose. Almost the polar opposite of my earlier method. It’s probably just my age, which is reassuring.

16 August 2011

Stimulating photons

Is it possible that some things are conceivable only in a certain language; that they have no description in the wrong tongue? In trying to understand how lasers work I keep butting up against the fact that they are “triggered” by photons of a suitable energy passing by, and the resulting stimulated emission occurs with the same frequency, plane, energy etc  as the input photon. But why is this so? Why does a passing blip elicit the release of an identical one? Is this phenomenon comprehensible in words? Or pictures? Or is maths the only form in which it can be conceived and communicated?

One explanation, by SM Sze in his afore mentioned “Semiconductor Devices” (1985) states (p. 254):
“When a photon of energy h v12 impinges on an atom while it is in the excited state, the atom can be stimulated to make a transition to the ground state and gives off a photon of energy  h v12, which is in phase with the incident radiation. This process is called stimulated emission. The radiation from stimulated emission is monochromatic because each photon has an energy of precisely h v12 and is coherent because all photons are emitted in phase.”

I do not mean to criticize Mr Sze but although that sounds like an explanation it does not explain to me why stimulated emission occurs, and what it is that is actually occurring. Further reading leads me to Raman scattering and in “Infra-red physics” by Houghton and Smith (1966) am not reassured by the comment with regard to Raman lines (p. 53): “Because the wave-mechanical description of a perturbed system involves all states of the molecule, the intensity of a Raman transition will be determined by a sum over states of products of the transition moments between states. This is too complicated for calculation even in simple cases. ...” 

Time to return to the drawing board, which in this instance is actually a zinc plate since the drawing is an etching. I submit to the frustrations of literal incomprehension, working instead in the realm of visual misrepresentation, and accept, for the moment, that maybe some photons are simply more stimulating than others.

26 July 2011

If something is truly creative then it is invisible as such, since nobody else can recognise it to be so. If you tell everyone what they intrinsically know already, they will think you phenomenally astute and insightful. It’s a matter of perception, which is a strong force to try to break through.

20 July 2011

Elemental homeopathy

Yesterday I set out on a voyage to draw a picture of silicon. I had wanted to draw the silicon atom (and to subsequently work up to the crystal structure) whilst envisaging the positions of the electrons / their orbitals, as I wish to come to a degree of understanding about semiconductors; the freedom, or not, of electrons from the silicon atoms in its crystal lattice appears to be of some import in that regard. 

Semiconductors can conduct a little bit of electricity (more than insulators, less than metals) as a result of loosely bound electrons in their chemical structures that can be liberated by absorption of energy from the environment in the form of heat; with increasing temperature intrinsic semiconductors become more conductive. I had been reading about semiconductor doping, this being a mechanism whereby semiconductor materials (for example silicon) can be altered through the addition of tiny amounts of other chemicals (the dopants) in order to make them more conductive. It’s kind of like elemental homeopathy. The doping materials can either be such as to add electrons to the semiconductor, making it more negative and hence called n-type dopants, or to stick some of the free electrons that exist in the semiconductor more securely into the chemical structure, effectively making it more positive and thus called p-type. P- and n- doping are fundamental processes in silicon photonics where they are used on a precise and minuscule scale to manipulate the passage of current through chips and wafers, etc. I had been fascinated to read that the addition of a single arsenic atom per million atoms of silicon increases the conductivity of the latter by 100,000 times. The arsenic atom has one free electron that it lends to the process (it is an n-type dopant), and yet this tiny addition accounts for such significant changes in the behaviour of the material. And so off I set onto the sea of electrons.

My journey took me deep into the world of angular momentums and exclusion principles, illuminations of virtual photons lighting my way, as I floated on surfaces of identical electron particle/waves. I had a smooth crossing of the Dirac Sea, since there was nothing there to cause wind or heavy weather, although the negativity got hard to bear towards its infinitely distant shores. Luckily the outcome from such monotonous negativity can only be positive, and all of a sudden the antimatter positron popped into existence. I journeyed on through radiant matter, and passed a few anomalous magnetic moments. Many hours of incomprehension further into the books and pages, all the while trying to assess which bits of this science are knowledge and which are model. I know that people have focussed beams of electrons for one reason or another, but no one has ever actually seen an electron, so know not what they have focussed. I read words telling me that an electron has a mass of about 0.00000000000000000000000000009 g, has an electric charge of -0.00000000000000000016 coulombs and a spin of a half. But I am also informed that electrons have no substructure and are hence assumed to be a point particle with a point charge and no spatial extent. I’m not sure how I can draw no spatial extent.

In order to see anything it seems that we need an illumination source that has a shorter wavelength than the dimensions of the thing we are endeavouring to see. For example, we can see using light since it bounces off the surface of visible things in such a manner as to convey surface texture and colour of objects, etc., to our eyes. Using a classic light microscope we can visualise objects with a resolution of down to about a tenthousandth of a millimetre, at which point the wavelength of visible light is getting to be of a similar scale to what we are looking at and it ceases to be able to discriminate surface variations. With an electron microscope the smallest dimensions visible are in the low nm range, about a hundred or so times smaller than things that can be seen under a light microscope. In order to look at an electron or a photon we need (a) for them to have a physical existence, and (b) something that can visualise down to the range of their physical size. 

And so I am back at wondering how, in the name of Art, to depict silicon’s electrons. Mentioning my problem to M later in the day she suggests that I simply put forward blank sheets of paper, and since she is an Art Historian I think I’ll take her advice.