Femto-science/technology

• From femtosecond chemistry to attosecond physics

• Ultrafast data communications

• Ultrafast imaging

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Imaging in the millisecond regime[Eadweard Muybridge –Galloping horse, 1887]

Flash photography- microsecond regime

‘Freezing’ of motion using short pulses of light

- e.g. 1 microsecond xenon flashlight

Novel apple sauce! [Harold Edgerton, MIT, 1964]

Prompt imaging in the ultrafast regime

Input

diffuse

snake-like ballistic

snake-like

ballistic

diffuse Output

An ultrashort laser pulse propagating through a scattering medium has ballistic, snake-like and diffuse components.

Images with femtosecond exposures![Valdmanis et al, Michigan]

Photograph of two crossed metal needles

(0.5mm diameter)

The needles viewed through a 6mm slab of raw chicken breast in ordinary illumination

‘Snapshot’ image of the needles using

femtosecond illuminating and

gating pulses

Imaging at terahertz frequencies

• Femtosecond laser pulse illumination of semiconductor switch

• Generation and propagation of terahertz radiation

• Spectroscopy & imaging using T-rays

T-ray image of packaged chip[Martin Nuss, AT&T Bell Labs]

• Plastic overlayer is transparent to T-rays

• Metal leads and silicon chip reflect or absorb T-rays

• 250 micron spatial resolution

Security-imaging with T-rays

Left: Shoe imaged with a standard camera

Middle: T-ray image reveals the presence of a ceramic blade and plastic explosives within the shoe

Right: Removal of sole exposes the hidden items[Image: Teraview]

Imaging of skin cancer using T-rays