An experiment for measuring the speed of light by measuring the distance between regularly generated optical pulses is described. The experiment utilizes optical feedback from a visible picosecond diode laser to accurately determine the distance between two successive laser pulses. The required setup is compact, and it does not implement either a fast detector or an oscilloscope. This experiment is suitable for an undergraduate physics instructional laboratory course or as an independent student project.
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See supplementary material at https://www.scitation.org/doi/suppl/10.1119/10.0007144 for a Mathematica code that uses Eqs. (5) and (6) to calculate the photon density function for the first eleven current pulses.
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2022
Author(s)
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