Claims of ‘unexpected and stunning new physical phenomena’ are rare in the abstract of a reputable scientific paper. But the latest report by photonics crystal pioneer John Joannopoulos and his group at MIT, soon to be published in Physical Review Letters, does not disappoint.
The researchers document the ultimate control over light: a way to shift the frequency of light beams to any desired colour, with near 100 per cent efficiency. ‘The degree of control over light really is quite shocking,’ comments photonics expert Eli Yablonovitch at the University of California, Los Angeles.
If the effect can be harnessed, it will revolutionise a range of fields – turning heat into light, for example, or prized terahertz rays. Right now, the only way to shift the frequency of a light beam involves sending an extremely intense light pulse – with a power of many megawatts or even gigawatts – along next to it.
This interacts with the first beam and alters its frequency, but the technique is expensive, requires high-power equipment, and is generally pretty inefficient. But when Joannopoulos and his colleagues Evan Reed and Marin Soljacic investigated what happens when shock waves pass through a device called a photonic crystal, they discovered a completely unexpected effect.
I’m just posting this because I like the word ‘photonics’ ;) But this is apparently really cool new tech.