Interactive simulations and visualizations augment the teaching and learning of quantum mechanics by making equations and concepts come to life. However, graphical visualizations are nearly always limited to a set of hard-coded functionalities. Text-based codes can offer a higher degree of flexibility, but only at the expense of steep learning curves or time investments. We introduce Quantum Composer, which allows the user to build, expand, or explore quantum mechanical simulations by interacting with graphically connectable nodes, each corresponding to a physical concept, mathematical operation, or visualization. Quantum Composer eliminates numerical and programming details while retaining accessibility, emphasis on understanding, and rapid feedback mechanisms. We illustrate its open-ended applicability through a series of examples in introductory and advanced quantum mechanics courses, student projects, and research environments.

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We often mention to students that they may prefer to use a mouse with Composer, especially those using macOS.
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This is described in more detail at <https://www.quatomic.com/composer/reference/faq/>.
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For example, to translate from Composer units to units used, e.g., in our quantum gas microscopy experiment, we take m = 1 to correspond to the mass of one Rb-87 atom and the energyscale E recoil to correspond to one photon recoil for a lattice with wavelength 532 nm. For more information, see <https://www.quatomic.com/composer/reference/quantum-composer-basics/units/>.
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