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Quantum information processing has been a very active area of research in the past few years. At the present stage of development in quantum computing, nuclear magnetic resonance (NMR) spectroscopy is considerably ahead of other techniques, and has been used in prototype quantum computers to implement different kinds of quantum algorithms and simulate other quantum systems. Center-supported research in Bing Fung's laboratory has led to a novel and interesting way to store hundreds of bits of information in the nuclear spins of liquid crystal molecules. This is accomplished by applying a programmable multi-frequency magnetic fields with low amplitude to manipulate the liquid crystal molecules, so that it is possible to excite a large number of coherent long-lived spin states simultaneously. By controlling the amplitudes of the harmonics in the excitation pulse, it is possible to encode proton nuclear magnetic resonance peaks to store information using binary codes. As an example, the sentence "The quick brown fox jumps over the lazy dog" has been be stored in the spins of a liquid crystal sample for tens of milliseconds. It is also possible to use a parallel search algorithm to find specific letters in this sentence without using parallel processors. In a technique called "molecular photography" Fung and coworkers have stored 32 x 32 = 1024 bit two-dimensional patterns, such as the gray-shaded diamonds above, in the spin state of a molecular system and retrieved the stored information as the stack of magnetic resonance spectra pictured. |
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