Photonic Metamaterials

Some of you may know that I am studying a degree in Physics!

I got given the opportunity to write an article on any area of science I wanted to potentially be published in the first issue of the Cardiff University science magazine... So I stuck with Physics and ventured into the area of Photonic Metamaterials!

I would love to have the opportunity to work within science communication as I have been told I have a knack for explaining complex phenomena to people who have little to no scientific background and I enjoy teaching people (but I'm not fond of little people so don't want to go into primary or secondary education).

Either way here is the Article I wrote for the magazine:

Do you want an Invisibility Cloak?

Sci-fi and fantasy films have invisibility cloaks throughout, from Harry Potter’s cloak to Klingon cloaking devices. The reality is that the science to make things invisible exists in the present day, although when I try to explain this to people they think I am pulling their leg. So, to convince them of this feat, I point out that it uses the negative refractive index and cloaking properties of photonic metamaterials, and then I receive some rather strange looks.

The field of complex photonic media (which encompasses photonic metamaterials) is a new area of physics, engineering, material science, and nanotechnology. So new that it is still very much experimental with some interesting results in a lab, but with no real life applications in use at the present moment. Unfortunately, due to technological limitations, items can only be cloaked against certain types of electromagnetic radiation (light), and these types of light are not within the visible spectrum. This means that your invisibility cloak will not turn you invisible to the human eye, yet. The closest scientists have been able to get to visible light is with microwaves. So, if someone could see in microwaves, your cloak would work and you would be invisible. The applications for this area are extremely varied; they can be used to provide solutions for telecoms, imaging, power, data-storage, computing, security and national defence.

You have probably read this and thought it all sounds good but perhaps you are still wondering ‘What on earth are photonic metamaterials?’ So I shall explain. A metamaterial is a synthetic compound that exhibits properties that are not seen in nature. Specifically, photonic metamaterials react with light in such a way that they can be used to manipulate light to achieve extraordinary results. Metamaterials, unlike materials found in nature which receive their properties from their chemical compositions, exhibit these bizarre properties because of the way their constituent parts are arranged.

Moving onto the invisibility part in detail, how does it work? It works because these metamaterials have a negative refractive index. This means that as the light passes through the material, it ‘bends’ in the opposite direction to light passing through a normal transparent medium, like a glass block. Using rings made of the material you can build up several layers surrounding the object you intend to render invisible.  Once you have sufficient layers arranged in the correct manner, the object should become invisible to the appropriate wavelengths. Although, unfortunately, a few problems have arisen when it comes to meeting the expectations on how well an invisible cloak should work. These problems are that the object is not perfectly invisible to the wavelength because there are imperfections in the layers and secondly, the cloak is restricted to only one wavelength and visible light is a broader range than just one wavelength.

The main challenge faced with making metamaterials is that the structures that give it the material its exciting properties need to be minuscule; they must be smaller than the wavelength of the electromagnetic radiation they wish to manipulate. Making such small structures requires advanced technology and this restricts the wavelengths to which we can cloak materials from, as I mentioned earlier. The size of the structures used in metamaterials need to be smaller than that of the waves they are looking to manipulate. Microwaves are centimetres in length, which means that the structures need to be of the millimetre size. By the standards of technology today, structures of this size can be manufactured. With visible light however their waves are a few hundred nanometres in size which makes them hundreds of thousands times smaller than microwaves, their structures need to be in the nanometre range. To create anything that is several nanometres in size is a technological achievement in itself. 

Jumping Through Hoops - Exams are stupid

An Exam is an assessment intended to measure a test-taker's knowledge, skill, aptitude, physical fitness, or classification in many other topics (e.g., beliefs). A test may be administered orally, on paper, on a computer, or in a confined area that requires a test taker to physically perform a set of skills. (or so says Wikipedia)

I have a few things to say on the subject! 

Thing Number 1

This is a fair enough method of confirming the knowledge, skill, aptitude, blah, blah of an individual as they perform and jump through hoops as the will of an examiner. Most subjects an exam is acceptable to assess the gained skills and to abilities required for the next level of study. But this angers me muchly as being a physicist and mathematician (self-proclaimed) doing my Advanced Levels and with our exams having a lot of questions with multiple ways of answering but the examiner wants us to use a specific method which is undefined by the question and never the way easiest or best way to answer.

Here is the last example that I encountered in Mechanics! Where a pair of forces are acting on the particle and you need to find the resultant magnitude and direction. 

This is the way the examiner wants it done:

This is how I would do it: 

But apparently this is too complicated and does not show an understanding of how the forces work ... somehow! Even though I've applied a trig identity and demonstrated that the two forces can be added end on end to give the resultant. Too confusing for you Mr Examiner ... well go learn what your marking and let me do it the easy and efficient way.

Thing Number 2

The point of a closed book exam seems pointless, although I'm still in education I can seem to imagine a situation (other than a kidnapping with gun to the head and have to do maths to escape) where you will have no computers, books, peers, calculators, so on so on to confer with to check your answers. So why make us do exams where things are recalled from memory and the applied although this may make you more efficient at your job at the end of the course it just means you have a load of Mathematical and Physical jargon crammed into your head which is easily accessible else where. So I feel that exams should be done as open book with notes and being allowed to bounce ideas of peers (although the flaw of being able to cheat is higher). Even so open book would make more sense! Even if they have to make the exams a little harder anyway.

Thing Number 3

Notation used in exams is terrible. I get told constantly by my maths teachers to write this and that make sure that its all spelt correctly blah blah blah blah blah! Well I use mathematical notation when I'm in a hurry because it cuts out the waffle but again I've been told not to use this as not all the examiners will know what it mean. When studying GCSE I got told when Timmy shared his sweets with his friends I need to write: 

6 Sweets distributed between 3 People 

Because what I would put is too confusing and I may lose marks for not putting what the examiner wants in the form he/she wants it! : 

6 Sweets ~ 3 People ... thats better, looks more math-sy 

The one piece of notation I get told off for most is Since/because and Therefore notation which is bizzare because they are used in most field not just maths. ∴ some examiners are stupid ∵ don't understand this notation



So the rant is over but I stand by my point of exams should be harder, open book, you should be allowed to use any method you know will work as long as your get the right answer, the examiner should be able to look at it and think that looks logical and award marks, and finally they should be trained in shorthand notation so that people can use it and still gain marks for doing so. so answer me why this does not happen as we have the time and man power to do so ‽

My outlook on 'Love' ...

I am a Geek/Nerd and I don't care what you think as you probably don't care what I think of you. Anyway 'love' the word that us massively overused and should only be used with caution because people get carried away with it. There is of course the idea that everyone has a soul-mate  'The One' if you will, so say this person is out there for everyone. Being a mathematician I have a quantitative view of the hopelessness here. I have been told my view is unique in that it is the most depressive and lacks self esteem and hope, so here we are:

• Assume everyone has that one person
• There are 7094804100 last time I counted but lets call it 7 billion (7 x10^9)  
• 'The One' is unfortunately is the last person you meet, or you have to meet everyone in the world to then realise who is the one ... or something along those lines 
• If you were to meet 5 entirely new people everyday without fail.

This means you would meet:

In           1 week                35 people

       1 month (4 weeks)     140 people

        1 year (365 days)     1825 people

This means that to meet all 7 billion people it would take:

7billion divided by 1825 ( number per year ) give a grand total of : 3835616.438 years 

Which is 3835616 years and 160 days ... 

But alas my thought doesn't end there as this is a massive number and no-one can live for that long (unfortunately) 

I also thought about how many people would you have to meet per day to meet 'The One' in a life time (80 years)

• You live for 80 years
• Same conditions as before
• You meet n people each day

In 1 year you meet 365 x n people

So the 7 billion divided by 365 gives if your life was 1 year long = 19178082 people per day

Over 80 years this means 19178082 divided by 80 gives per day for 80 years = 239726 people

So this means every day you must meet that many people

This gives you 9988.58 people per hour

166.48 per minute 

2.77 per second

So everyone you meet will get a grand total of 0.36 seconds of your time! 

Think this is the end? Wrong again my friend. Both of these thought experiments assumed that the population is constant and people lived for ever. We all know this isn't true if only it was, we would ... that's besides the point but carrying on. 

So lets change the parameters slightly and say that every year 10 million people are born and 4 million die. This gives us a growth of 6 million people in year 1.

WARNING! Horrible differential equation maths coming up skip if you want to

Population grows exponentially:

P = Ae^(kt)

Where P is population and t is time(years)

with 7 billion in the world at t=0 

and grows by 6 million in a year t=1

P=7E9 x e^(0.000856775t)

This is my model that shows the growth. It predicts that even if you were to meet 10000 per day you would never meet everyone as the growth would escape the linear meeting of people.

So you would have to go polynomial on it. Meeting a certain number times more people every consecutive year. 

I looked for the intersection of my model graph and a graph of y=x^(11/2) to see that within 63 years the graphs cross over meaning you have met everyone in the world so far.  

In this case you would be looking at every year you would have to meet 5 and a half times more people that the previous year for 63 years in order to meet everyone.

The end ... I guess

Just as an after note you could have not met you true love as she may have died or not been born by the time you come to pass away. As calculating this would be probability best as it would all be about timing/chance and not time. 

Sorry if this has dampened anyone's mood on love, keep looking/trying and you'll find someone close enough to 'The One'.

Disclaimer: if this has upset you in any way shape or form I can't be held responsible as you read it on your own accord and should man the hell up

Personally the Few Most Amazing Jobs Out There

Because I am going to University later this year I've been thinking about jobs to do once I leave and being an ambitious person all of them are quite out there and really seem far fetched to those of us smaller vision (not to offend). As a physics student all of these jobs are physic and sci fi related, enjoy.


1. Asteroid Miner!

The latest of my finds which seems like the coolest thing ever, but is not quite what it seems like on the tin or in the old sci fi films. As much as I would like it to be a job where I would fly to the asteroid  land on it with a pick axe or super high tech mining equipment and go to work, its not. Although the competion seems very aggressive as one company 'planetary resources' released its plans and within a few weeks they had already got over 2000 applicants. There plan is to mine near earth asteroids for platinoids ( Ruthenium, Rhodium, Palladium, Osmium, Iridium, and of course Platinum. If you didn't know). 


So what does this job entail? 


There seems to be 3 mains areas:

Systems Hardware Engineers, working on the embedded systems such as micro-controllers and data acquisition, design for of the front end for telemetry and other environment specific sensors.

Navigation and Control Engineers, Working on, as it says, the navigational and control aspect of the spacecraft. This will also include calculating its flight path and consulting on every stage of the development from initial design to launch.

Ground and Flight software Engineers, Again the job is as it says, running the life-cycle of the embedded software systems. This includes again the consultations on every stage.

http://www.space.com/15686-asteroid-mining-jobs-planetary-resources.html
http://www.planetaryresources.com/mission/

2. Any Job at CERN is a job worth having!

CERN is the coolest place on the planet in my own eyes. Being massively interested in particle physics, and the best thing about it is that my school has got a trip running as we have been given free pass for a tour. I was the first chosen to go as the only physics student out of 7 that has a massively over-keen interest in the field. Once I've done my degree and possibly a P.h.D I am looking to apply for a fellowship, as it is roughly where I'm working towards. The research here 30 years ago was focused and finished on the W boson as they discovered its existence and then they had turned their attention to the Higgs Boson (the quanta of the higgs field). Recently finding evidence to a high significance for its existence. 

So what does this job entail? 

There are hundreds of job at CERN with it employing thousands of people to run and maintain the systems. my favourite 2 jobs would have to be:

Theoretical Physicist, needing a P.h.D in Physics makes it sounds fun all on its own (to me at least). The job entails that you will have to develop new theoretical ideas aimed at understanding the fundamental forces of nature, Develop the relevance of the experimental programmer and take advantage of the large laboratory available  Finally you will have to contribute to the general scientific culture though active participation in training programmes and promotional events on site. Have to admit that sounds like my dream job. 

Process operators on CERN's technical facilities - cryogenics, cause who doesn't love a job in cryo-physics. That serious lack on energy makes systems more fun and cool (pun intended) to work with. The systems of the LHC constitute nearly half the worlds stock of liquid helium liquefiers in order to keep the equipment as near to 0K as possible. your job would be to maintain these systems!

https://ert.cern.ch/browse_www/wd_portal.show_page?p_web_site_id=1&p_text_id=1

My Intro to the Blog-sphere

I like to think I'm unique, but I'm defiantly not normal ... How many more like me? I can't say unfortunately  though I wish I could. 

I consider myself a physicist as I am madly in love with the field, currently studying A levels and hopeful a Degree later this year. Got my own telescope, and I've been looking for a reason to build a Trebuchet! 

In my studies a lot of number crunching comes up and I take that and apply it to real life. I use the numbers to apply a pessimistic view to others peoples world as the numbers look hopeless. Whilst trying to maintain an optimistic outlook on my own life.

I am an avid RPG gamer although I've recently been dragged, by friends and family, into the realm of FPS gaming. The elder scrolls series is where the love began and it eventually progressed to the online world as I started to play World of Warcraft, Star Wars the Old Republic, and various games on Steam. 

I have been called every name under the sun from a communist to an extremist, from a geek to a player, and from a genius to a retard. So I take this a sign of unpredictability in my action, you should to. 

My taste in music, food and general culture is vast to say the least. I like all types of music from the lovely sounds of classical tunes to the headbangyness of metal (headbangyness is a real word from now on, go forth and use it). With food I am fearless anything new I am not scared to try, from shark to squid, from centipede to monkey brains. As I travel the food outlines the culture so well it seems almost rude not to try. 

I travel a lot, all around the world and would like to go a lot of places I haven't had the chance to. Ive climbed several mountains and kayaked various rivers, sailed across vast expanses and traversed many plains. Oh, im sounding quite poetic, guess that outlines my passions for adventure. 

Normally I don't sound so formal, but its most likely a confidence issue of taking what is in my head and putting it onto the internet for all to gawk at.

Sleep well children of the internets