hyderabad researchers in the united states and korea have brought light to a complete standstill in a crystal the pulse is effectively held within the solid ready to be released at a later stage according to a report in nature science update a crystal that holds light could facilitate quantum computing said philip ball author of the report normal computers store information in simple binary from is and os in electronic and magnetic devices stationary light pulses can encode information in more sophisticated ways that use the laws of quantum mechanics making information processing more powerful light moves at 186000 miles per second through empty space and was first stopped in its tracks at the beginning of last year in that experiment a vapour of metal atoms cooled close to absolute zero was shown to act like molasses on the passing light beam now philip hemmer of the air force research laboratory at hanscom air force base in massachusetts and his colleagues have halted light in a crystal of yttrium silicate containing a few atoms of the element praseodymium lightstopping solids would be much easier to incorporate into faster more powerful computers than extremel cold gases so the advance could aid information technology in much the same way that solidstate diodes and transistors made electronics more compact and robust than it could be with vaccum tubes says ball light slows down very slightly when it passes into any substance from a vaccum the greater the refractive index of the material the slower the light becomes to make laser light travel very slowly researchers create substances with immense refractive indices hemmers team used a second laser beam to excite atoms in a substance to new energy states light can be considered to propagate through a material by being sequentially absorbed and reemitted by atoms the second beam manipulates this process so that it becomes more and more difficult for the light to make the step from one atom to the next the second beam couples the light pulse to the atoms when shackled to these heavy objects the pulse comes to rest and all its energy is transferred to the atoms a light pulse that is brought to a standstill is not destroyed the atoms remember it so the pulse can be regenerated by changing the intensity of the coupling laser to allow the atoms to reemit photonsthe particles of which light is composed