B. Lenssen and Y. Bellouard, "Optically transparent glass micro-actuator fabricated by femtosecond laser exposure and chemical etching," Applied Physics Letters 101, 103503 (2012).
 
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We introduce a new method to investigate localized volume variations resulting from laser exposure. Our method is based on the measurement of fused silica cantilevers deflection from which we calculate the effective stress and density variation in laser-affected zones. Specifically, we investigate density variations in fused silica exposed to femtosecond laser exposure in the regime where nanogratings are found. We demonstrate that a volume expansion is taking place in that particular regime. (Download / PDF)