22 March 2011

Increasing the clarity of the unclear clearly

The light half.

Day 44. (already) A brief meeting with the boss. What a difference ten minutes makes. He has been reading the blog and is evidently appalled by the woeful lack of understanding and factual content therein; he specifically mentions the unclear “Clearly, this implies that...” which I referred to some weeks ago. It’s time for me to learn something. Only a few minutes later I leave the office with real comprehension about that formerly incomprehensible page turn (not least that the vertical lines either side of the letter r, the r representing the reflection coefficient, are the math shorthand for ‘the magnitude of’, so I can now at least write out the sentence in English rather than mathematics: Clearly this implies that the magnitude of the reflection coefficient is equal to one. (Why didn’t he just say that in the first place?)). But I’m also a little sad to have lost the infinitely intriguing imagined interpretation of imaginary numbers, having had them tied down to the mundane conceptual realities of axes on a graph (although as I write the understanding of why one would want to map the imaginary on the perpendicular axis to the real is again disappearing in a fog of misunderstanding, so that’s ok). Anyway, for the moment I don’t think it’s necessarily important to know the mathematician’s rationale for the perpendicularisation of real and imaginary, of import is that electronic engineers use the fact that real and imaginary numbers are plotted on the x- and y- axes (respectively) as an analogue for impedance in circuits. In capacitors the voltage and current are 90 degrees out of phase, and so these components (as well as the roles of resistors and inductors, the three collectively comprising impedance) can be mapped out on the axes (resistance is represented by the positive x-axis (the real equivalent), inductance by the positive y-axis (the imaginary equivalent), and capacitance the negative y-axis (imaginary equivalent). Bother, that seems to describe the roles of three of the four axes, but begs the question of what it is represented by the negative x-axis?). Anyway, it is evidently clear that by this means the overall impedance of a circuit can readily be calculated. You see?
As I write I am sitting on the train heading back home – again my reserved “window” seat was next to a piece of non-transparent train structure that largely obscures any view of the outside world, and someone else was already sitting in it anyway (having evidently also switched the seat tickets around to make it look like his!); but he is welcome to his falsely acquired sliver of view. It’s almost dark anyway, and I am now sitting at a forward facing window seat at a table, where I have spread out all over the place, and with relative acres of darkening glass next to me. I am riding high on the knowledge that I’ve acquired knowledge, and desperately trying to think of what to ask for the tutorial we have timetabled for next week; it seems that this art tomfoolery can remain obdurately obfuscated no longer.

16 March 2011

Miniscule devisive shoes

About time.

I left the house at dawn this morning, at that very moment of its occurrence. The blackbirds were just starting their chorale and the sky was lightening. As I travelled to the station the mist rested in the valleys, and hung in the trees on the hillsides; approaching the turning, a long view through to a low east horizon showed a disc of deep luminous red hanging within the grey fog, the sun making its local debut for the day, stunning. Even as I saw it the news on the car radio reported of the evacuation of the Fukushima Daiichi power station because of a “spike of radioactivity” following explosions and a fire. On hearing the news I am stupefied in sadness and horror – what we do to ourselves, what we do to this earth.

As I write I am en route back up to the lab, a two day stint of residing. The train creaks and trembles as it rattles along the warming tracks, the day outside increasingly sunny, the warmth and light burning off the vestiges of water vapour, giving the day a bright golden clarity. I have decided that the time, being half way gone, is apposite for revisiting the copy of nature photonics that Graham handed me that first trip to the University (the Silicon Photonics special, August 2010, volume 4, number 8). 

[Low tide at St Germans as we pass, the muddy slivers of estuary snaking between the breast-like hummocky hills.] 

I can still remember my first naive fumblings between its sheets, sitting in the doctor’s surgery waiting room, trying to make some sense of it and recording my wonder at the words. I wonder how the experience of the time spent so far amidst the silicon photonicists will have affected my abilities in that realm.

Even as I open the covers I can’t help the smile as I read the words “Towards fabless silicon photonics” – doesn’t it sound like they’re trying to take the fun out of it? and I’m afraid that “Mid infra-red photonics in silicon and germanium” just makes me think of the silicon geranium photos I have taken. But enough mucking around, time to redive into Reed, Mashanovich, Gardes and Thompson, and their small world of silicon optical modulators (pages 518 to 526).

[Unbelievably low tide on the Plym as we pass, the sunshiny mudflat thronging with birds; it is the equinox this weekend, so I guess we’re due big springs soon, but the moon last night was a bright and clear more-than-semicircle, so I should think it’s pretty much fully neaps. Perhaps we are passing at the moment of its lowest ebb.]

In the review abstract they report that “Modulators have been improved dramatically in recent years, with a notable increase in bandwidth from the megahertz to the multigigahertz regime in just over half a decade.”, which I think sounds pretty amazing when you think that such a shift must be supported by actual physical technological and fabrication developments (this latter the word responsible for the dour, truncated fab in fabless), as well as the conceptual and ideological drivers involved.

[I just went and squeezed in next to a guy facing the right way in order to take my customary photograph of the “Teignmouth Electron” as we passed (a long series of muzzy and largely imperceptible images of a
(currently rather rapidly and man-assistedly) decaying boat on the banks of the Teign). This “Teigmouth Electron” is a boat that is reminiscent to me of the real Teigmouth Electron, which is apparently slowly dissolving on a Caribbean beach, and to which I was introduced by a piece of Art made by Tacita Dean. In the book about it she tells the story of Donald Crowhurst who went out alone onto the watery surface of this world, on his final earthly journey, in the little vessel, on a partially-faked round the world race. It is a haunting tale that is beautifully told by her, delving into the realms of hope and expectation and time. An inspiring work. Just before he got off at Exeter the man came to thank me - he’d looked it up on the internet via his phone and thought it was a great picture (I recommended he look up the book and read the words...).  Very satisfying to have passed on the awareness of something wonderful, especially so geographically close to the location of the doppelganger craft.]

Back in the journal I grasp what the abstract is trying to tell me, although there are still some words that are yet mysterious. I am not clear as to what the modulation depth refers (I assume it is more than simply a physical depth in the wafer), and do not know how the energy requirement per bit can be altered, although with such increases in numbers of bits presumably it is something of a major consideration. As for the size of the device footprint, I do not know it but assume, given the scales at which they are working, that it must be very tiny, and very fast; miniscule devisive running shoes?

7 March 2011

Art in the lab

I had thought that suffering three years of what they refer to as teaching on a fine art BA had finished, once and for all, any desire for me to continue a relationship with formal education. However, last week I became the proud recipient of a certificate that enables me to be in the presence of multifarious lasers, and with only a little more tuition I may yet even be allowed to switch one on. The laser course, at a mere one and a half hours, was not the most painstaking of learning processes, and yet my name is printed on the certificated page (in a different font to that surrounding it) and the qualification valid for three years. Not only that but it was sunny pretty much all day. If I do ever work out how lasers work (and perhaps should mention that the jocular Spaniard assured me formerly that they shouldn’t) I will let you know. I had hoped that this blog post might be learned and profound (dream on?!), possibly even adding some insight as to how lasers do work, for example, since it marks the half way point of my residency in the silicon photonics lab. But instead I’m rather in the mood for a bit of Art.

For the lab meeting on Thursday I festooned the walls of the meeting room with photos and drawings that are some of the products of my work during the time I have been at Surrey (take a look in a couple of days at www.emmahambly.net for images, which will be placed there imminently!). They are a plethora of things, and some to me are beautiful. [A note to scientists at this point, the term beautiful was basically illegal at art college when I was there (one and two third years ago), since it was judged very low brow to make things that have aesthetic appeal which can be deemed as such. However, there may have been a subsequent cultural shift, as much more recently (one and a third years ago) a Turner Prize winner’s wall drawings were positively described as beautiful by the initiated critics.] Having explained to the lab group what the works were all about, it was time for a pop up exhibition in the ATI, and so I opened the doors to the science masses. There followed numerous interesting conversations, about photography and dyes and light emitters, electronics in paper, etc, which have left me with many fascinating avenues, which, I imagine, will not get explored to any great depth as a result of constraints of time. [Although I have managed to bend time on several occasions, I am still not entirely able to manipulate it fully to my advantage, and it seems that I’m bound by the laws of mundane physicality most of the time, and so sadly currently consider my ability to explore the world as being finite.] A hit with the aesthetic judge (a member of staff from the Arts office at the University) were the rather abstract Polaroid photograms; some having been illuminated by the naturally spectral light of a full moon, and some using electronically derived illumination (i.e. my phone screen light). And I think the boss liked the glass piece I made that is inspired by the integration of electronics and optics, and loosely illustrates a ring resonator. This week I am to take the same objects and images to an art audience (some students at Plymouth College of Art), and am intrigued to see  whether they garner a different response there. For now I am off to work on the big drawing I am making, and to see if I can master the stretching of time.

Here I planted some flower seeds yesterday, and even this morning, beneath the rays of the spring sun passing through the greenhouse glass, I can sense the burgeoning awakenings in the warm dampness of their earthy beds.