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Engineers at Stevens Institute of Technology have developed a technique to optically modulate the frequency of a laser beam and create a signal that is disrupted significantly less by environmental factors, says Dr. Rainer Martini. The research provides for enhanced optical communications, allowing mobile units not tied to fiber optic cable to communicate in the range of 100 GHz and beyond, the equivalent of 100 gigabytes of data per second. Eventually, the team hopes to extend the reach into the terahertz spectrum. The frequency or amplitude modulation of middle infrared quantum cascade lasers has been limited by electronics, which are barely capable of accepting frequencies of up to 10 GHz by switching a signal on and off.  Marini and his team have developed a method to optically induce fast amplitude modulation in a quantum cascade laser to control the laser's intensity. Their amplitude modulation system employed a second laser to modulate the amplitude of the middle infrared laser, using light to control light. The current detector is only capable of detecting frequencies up to 10 GHz, but Dr. Martini is confident that a new detector will make the system capable of much higher frequencies. With an optical system that is stable enough, satellites may one day convert to laser technology, resulting in a more mobile military and super-sensitive scanners, as well as faster Internet for the masses, says Martini. Ref.: "Optically induced fast wavelength modulation in a quantum cascade laser," Applied Physics Letters, July 7, 2010.

LEDsThe strange quantum state of entanglement isn't just challenging to think about, it's hard to create. This "spooky" phenomenon-in which two particles are linked, even if they're separated by distance-can be created by scientists in the lab using bulky lasers. But scientists published a study in Nature today in which they created a light-emitting diode (LED) that produces entangled photons.

It's a sports car few people will be able to get their hands on. In production since last December, only 500 Lexus LFAs will be produced and they were already sold out in early June 2010 (see photo below). But it's not just its top speed of 325 kilometres per hour that's attracting buyers. The car is being used as a test bed for newly-designed parts made from carbon fibre and plastic. Compared to steel or aluminium, it makes the car stronger and lighter but producing these components is much more time-consuming: only one car is currently being assembled per day. One of the key technologies being used is a high-tech circular loom, guided by lasers, that can weave 3D objects (see video above). The machine's futuristic design attracted lots of media attention two years ago, but the video was pulled for fear it would expose company secrets. Now Lexus is revealing how the loom is being used to create complex 3D parts with varying thicknesses and curved shapes. For example, it can create roof rails by weaving fibres around a core, two layers at time, until twelve layers later a hollow roof rail is produced. The piece can then be moulded and injected with resin to create the finished part. The machine was also used to create the car's chassis and front pillars as well as the steering wheel.