Ian Sandal

Favourite Thing: Testing out new ideas, by making new samples and seeing if the theory works!



I went to School at Culverhay School, Bath (1992-1999), I then went to Cariff University (1999-2003 and 2003-2007)


A Levels (Physics, Maths, Economics), Degree (MPhys(Hons) in Physics) and PhD (Physics)

Work History:

I’ve worked for Philips (at there research labs in Holland) and I currently work at Sheffield University

Current Job:

Postdoctoral Research Associate


University of Sheffield

Me and my work

I make and study new materials for lasers or that can detect light.

I work with a type of materials known as semiconductors, these are very special materials which when very cold behave like an electrical insulator (like wood or rubber), however as they get hotter they behave more like an electrical conductor (like metal wires). The most common type of semiconductor is Silicon, which is used to make all electrical chips and components, however there are many other types of semiconductor materials.

Many of these materials also have a strong relationship with light and I use this effect to design and make lasers and detectors for use in lots of different ways.

To make these devices different semiconductor materials are stacked on top of each other, in a similar way to which you might make a sandwich (the bread is one material, the butter another, and so on). Some of these semiconductor sandwiches can have many different layers (10 – 100) to allow both the light and electricity to be controlled as we want. To then make a laser we put an electrical voltage across the “sandwich” the electrical charges are then converted into light ! The color of the light made is controlled by the semiconductor layer in which it is made (so each material will give off a different color light. These types of lasers are used in lots off applications every day some examples include: DVD Players (Red Lasers), Blue Ray Players (Blue Lasers), Laser Pointers, Medical Testing, and internet fiber optics.

To make a detector from these materials we just operate them the other way round. We shine light on them and this makes an electrical current flow ! – The brighter the light the higher the current that is made, so we can tell how bright an object is. These are commonly use in solar panels and CCD Cameras (like on your mobile phone).

Visible light is just a small section of what is known as electromagnetic radiation. This is a wide range of waves which covers Gamma Rays, X-Rays, Ultraviolet Light, Infrared Light and Radio Waves! So far most of the lasers and detectors that have been made work with visible light, however if we can make lasers that create these other types of radiation (and then detect it again), there are many new uses we can find.

For example if we pass certain colors of infrared light through a person we can see if they have cancer! In the same way we can shine light onto a unknown object and tell what it is – this would be really good in airports as we could then see exactly what was inside each bag.


My Typical Day

Designing, Making and Testing Devices

My days can be quite varied as there are lots of steps involved in making new devices and getting them to be as efficient as possible.

The first stage is to design the devices, this involves computer codes and models so that we can test lots of different idea out to see what looks like it will work – but the computer programs are only as good as our theory !

The next stage involves making the devices! For this I have to go into an special laboratory where everything is ultra clean – this is needed as otherwise we might get dirt or dust on a device which might alter its performance. This means that I have to wear special clothing to help keep things clean myimage1

In this lab we put metal onto the devices (so that we can solder wires onto them and connect them to circuits) and use different chemical (Acid!) treatments to change the performance. myimage2 myimage3

We next have to test how good the devices are, for this we have lots of different labs to perform electrical measurements (i.e. applying voltages and currents across the devices) and optical labs where we can see if they work as lasers (or detectors).

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We then compare these results to our first computer models to see if we got the result we wanted! If not we have to work out if our models are wrong, or if something went wrong when making the devices.

What I'd do with the money

I would like to buy optics packs for school Children in developing countries

2015 has been named the International year of Light ! – This is an UNESCO (Charity) initiative to celebrate and promote light and its uses. As part of these celebrations there is a program to send optics packs (with LEDs, lenses and mirrors) to disadvantaged schools around the world so they can perform optics experiments in their classes and learn about light.

As I work on making light this seems a great way to use the money and spread the excitement.

My Interview

How would you describe yourself in 3 words?

Positive, creative and Fun

Who is your favourite singer or band?

The Manic Street Preachers

What's your favourite food?

I like all types of food, I can’t really pick just one

What is the most fun thing you've done?

Hiked over the Andes in Peru and then sailed down the amazon

What did you want to be after you left school?

I had no idea what I wanted to do

Were you ever in trouble at school?

Sometimes …

What was your favourite subject at school?

Science, I always have been a bit geeky

What's the best thing you've done as a scientist?

Probably the first time I got to present my work at a big conference in America. It was towards the end of my PhD and was really exciting (and a little scary) to be able to stand up infornt of lots of famous proffessors and tell them all about my work

What or who inspired you to become a scientist?

I was always very inqusitive as a child and wanted to know how things work, but the real drive probably came after I read a novel about Alan Turining and the Enigma code when I was a teenager

If you weren't a scientist, what would you be?

Probably an Engineer

If you had 3 wishes for yourself what would they be? - be honest!

To be happy, to always enjoy my job and to be able to spend lots of time with my family

Tell us a joke.

I’m reading a great book on anti-gravity. I can’t put it down

Other stuff

Work photos: