Willing waves as you wish:
technologies involving light and sound

Searching for new planets

Searching for new planets
1010 times faster than this!

1010 times faster than this!
Laser beam

Laser beam
100000 Hz ears

100000 Hz ears
Ripples on crystals

Ripples on crystals
Sound wave reflection in a nanostructure

Sound wave reflection in a nanostructure
Simulating sound in phononic crystals

Simulating sound in phononic crystals
Sound in a phononic crystal (angle-radius plot)

Sound in a phononic crystal (angle-radius plot)

* Click image to enlarge.

When you hear the word ‘wave’, most people think of surfing or an elaborate hair style. Arguably more important to human life are however light and sound waves that support our two primary senses.

Light and sound waves are being put to good use in our Graduate School.

Incredibly fast: you struggle with your eyes to see movement in 100 milliseconds; how about trying to distinguish 10-15 s! This is being done and we have on different occasions achieved the world’s shortest visible light pulses.

Just like an expensive camera that can freeze high speed motions, our 10-15 second camera can capture molecules in motion or whizzing electrons in atoms.

Incredibly high pitch: with your ears you can distinguish sounds up to 20000 cycles/second (Hz). Bats can hear up to 100000 Hz. We are using sound pulses up to 1000000000000 Hz! (1012 Hz) to look into tiny structures with micron or nanometer (10-6-10-9 m) dimensions. These micro- or nano-structures are used in everything from electronics to cellphones.

We also use these sound pulses to watch tiny ripples travelling on crystals, just like water waves travel over the sea, but a million times smaller.

Incredibly complicated: sound in regular structures, or phononic crystals, is forced into vibrational patterns known as Bloch waves. Interestingly, such waves lie in frequency ranges called bands, there being gaps where no waves can pass. We are investigating both experimentally and theoretically how sound travels in these novel structures.

Incredibly far: using light that has travelled across the cosmos we are searching for new extrasolar planets with long baseline interferometry. In this way we eliminate the light from the host star to home in on the planet itself.