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"It works by emitting a burst of light from a femtosecond laser that reflects off visible surfaces - such as an opaque wall - onto objects that are hidden from the camera's direct view. The light then bounces off the object before ultimately making its way back to a detector. This process is repeated a number of times with the laser targeted at different areas of the reflecting surface." nice video

Duncan aND Lionel please check this one

Spacecraft equipped with lasers powered by light from the Sun are our best defence against incoming asteroids, say aerospace engineers

"When a control laser is fired at the crystal, a complex quantum-level reaction turns it the opaque crystal transparent. A second light source is beamed into the crystal before the control laser is shut off, returning the crystal to its opaque state. This leaves the light trapped inside the crystal, and the opacity of the crystal keeps the light trapped inside from bouncing around, effectively bringing light to a full stop." is the simple explanation, but I am not sure how this is actually possible with the current laws of physics

There are two ways to make slow light: material slow light and structural slow light, where you either change the material or the structural properties of your system. Here they used EIT to make material slow light, by inducing transparency inside an otherwise opaque material. As you change the absorption properties of a material you also change its dispersion properties, the so-called Kramers-Kronig relations. A rapid positive change in the dispersion properties of a material will give rise to slow light. To effectively stop light they switched off the control beam, bringing back the opaque state. Another control beam is then used to retrieve the probe pulse that was 'frozen' inside the medium. Light will be halted according to the population lifetime on the energy level (~ 100s). They used an evolutionary algorithm to find an optimal pulse preparation sequence to reach close to the maximum possible storage duration of 100s. Interesting paper!

So it is not real storage then in a sense, as you are stimulating an excitation population which retains the phase information of your original pulse? Still it is amazing that they could store this up to 100s and retrieve it with a probe pulse, but light has never been halted.

"We have made optical systems at the microscopic scale that amplify light and produce ultra-narrowband spectral output," explained J. Gary Eden, a professor of electrical and computer engineering (ECE) at Illinois. "These new optical amplifiers are well-suited for routing optical power on a chip containing both electronic and optical components.

Lasers + diamonds --> simulate pressure of thousands of atmospheres on planetary cores!

As a side note, this is also being used as method to create a hypothetical substance called 'metallic hydrogen'. At such high pressures, hydrogen itself should become superconducting at room temperature and thus of tremendous interest...

this gets into into interesting power ranges

Can we have one?

They say they create 2 GeV electrons in a very small setup. However the laser they use is more than 10 meters in length. Still a really nice result.

Compared to a 27km circumference this is major achievement and it is indeed already foreseen that future colliders will include this technology as beam fillers and pre-accelerators at some point. The technique is quite elegant and a lot more energy efficient. Nevertheless, there are also thoughts that future particle colliders might actually go towards space and study collisions orginating from extremely energetic cosmic particles

Imagine a material that only admits thermal conduction for certain temperatures. Martin Maldovan from Georgia Tech holds a tiny thermoelectric device that turns cold on one side when current is applied. Recent research has focused on the possibility of using interference effects in phonon waves to control heat transport in materials. These are exciting news (see Nature Materials paper here http://www.nature.com/nmat/journal/v14/n7/full/nmat4308.html). Heterostructure research lead to outstanding new possibilities when applied to electronic transport (e.g. in quantum well and quantum dots) and to photonics (e.g. Quantum Cascade Laser tunnable lasers). Apparently the time has come to see selective thermal control in this way! Truly exciting!!

I assume that our fancy colour printer also have this "feature" ... 

next step taken .... after they won the power beaming challenge ... fantastic team!

terahertz lasers controling the spin of electrons ....

another hill to climb (in reference to a metaphor of a recent post)

"we report the high-pressure, high-temperature synthesis of a diamond aerogel from an amorphous carbon aerogel precursor using a laser-heated diamond anvil cell"

so what ...?

Depending on its properties it might be interesting as an ablative heat shield material.

July 14, 2009 NASA Dryden Flight Research Center, Edwards Air Force Base, Mojave, CA 6 Teams [KCSP, LM, USST, NSS, McGill, U MICH] 1 km vertical raceway, laser-powered vehicles $2,000,000 Total prize purse (two levels)

What would you do if you owned the world's most powerful laser? The US government is hoping to use it to achieve the ignition of thermonuclear fusion in the lab for the first time. Nature Photonics spoke to Edward Moses of the National Ignition Facility t