Ion traps are almost magical to watch, yet the underlying physics encompasses little more than basic mechanics and electromagetism, what is now covered in first-year physics courses at most universities. This experiment uses a set of three different electrodynamic ion traps (also known as Paul traps) to capture 25-micron-diameter charged particles in air. The particles are illumnated with green laser light, making them easily visible to the naked eye. Students explore aspects of the trap dynamics, observe Coulomb crystals, and make quantitative measurements of particle charges and masses, as well as picoNewton trapping forces!  

This affordable experiment is a HUGE crowd pleaser!  Even students with no physics background enjoy the ion trapping experience, and everyone learns a great deal from it. Please click here for additional information.

Here you can find detailed instructions for building your own electrodynamic ion traps, allowing you to demonstrate this fascinating physics using a variety of trap geometries you design yourself. It's easy, it's fun, and everyone enjoys watching these levitating particles dance!

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A compact, table-top instrument that allows students to assemble a basic Michelson laser interferometer, characterize its performance, and then demonstrate picometer displacement sensitivity with 10-cm arms.  (That's 1/100th of an atom; like measuring the distance from New York to Los Angeles to the width of a human hair!)  Placing and aligning components teaches students about modern optical hardware and lasers; locking the interferometer at its most sensitive point teaches feedback and servo control; measuring the displacement sensitivity teaches modern signal conditioning and phase-sensitive detection. No signal generator or lock-in required; all you need to add is your digital oscilloscope.

This is a full-featured laser interferometer that goes far beyond counting fringes. It is a hands-on instrument with great teaching potential, and your students will love it!   
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Students learn all about high-Q harmonic oscillators and clock physics in this modern, lively experiment.  The test mass of the torsional oscillator is a rare-earth magnet, and applied magnetic fields are used to drive the oscillator and change its spring constant.  Laser-based diagnostics allow students to measure many aspects of simple harmonic motion. The instrument includes a "clock mode", where feedback produces self-sustaining oscillations, and precision measurments of the clock frequency allow another series of experimental tests.

This compact apparatus offers many enlightening experiments that can be done with relative ease, giving students an excellent tour of the fundamental physics of harmonic motion.  Please click here for additional information.