To activate the altered neurons, they usually use a laser tuned to the proper wavelength and pipe the beam through a fiber-optic cable implanted in the brain tissue.

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The wavelength of the laser light can be tuned to interfere only with u-235 and "excite" the molecules, raising their energy level.

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Moreover, such a laser can be fine-tuned over a smaller range of wavelengths simply by varying its temperature.

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The high average power infrared Free Electron Laser (FEL) provides intense beams of laser light that can be tuned to atmosphere-penetrating wavelengths.

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