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PyLCP: A python package for computing laser cooling physics



Stephen Eckel, Daniel Barker, Eric Norrgard, Julia Scherschligt


We present a python object-oriented computer program for simulating various aspects of laser cooling physics. Our software is designed to be both easy to use and adaptable, allowing the user to specify the level structure, magnetic field profile, or the laser beams' geometry, detuning, and intensity. The program contains three levels of approximation for the motion of the atom, applicable in different regimes offering cross checks for calculations and computational efficiency depending on the physical situation. We test the software by reproducing well-known phenomena, such as damped Rabi flopping, electromagnetically induced transparency, stimulated Raman adiabatic passage, and optical molasses. We also use our software package to quantitatively simulate recoil-limited magneto-optical traps, like those formed on the narrow $^1$S$_0\rightarrow ^3$P$_1$ transition in $^88}$Sr, and theoretically explain the unique limitations of similar magneto-optical traps in $^87}$Sr.
Computer Physics Communications


laser cooling, optical Bloch equations, magneto-optical trap, optical molasses, simulation, software


Eckel, S. , Barker, D. , Norrgard, E. and Scherschligt, J. (2021), PyLCP: A python package for computing laser cooling physics, Computer Physics Communications, [online],, (Accessed June 19, 2024)


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Created September 9, 2021, Updated October 14, 2021