Hussar software, developed by scientists from the Polish Academy of Sciences’ Institute of Physical Chemistry and the University of Warsaw, can be used to perform the complex computations necessary to mathematically describe the interactions that can occur when beams of ultrashort laser pulses running in the same direction intersect with each other at an angle. According to the team, the latest version of Hussar software makes it possible to perform these calculations on a laptop — eliminating the need to engage entire computer clusters to carry out the appropriate simulations. The Hussar software is free and is available on the project’s home page. With the Hussar program, you can now efficiently model the interactions of femtosecond laser pulses traveling at a mutual angle of up to 140 degrees. Courtesy of IPC PAS. “The changes introduced in the latest version of the Hussar program are radical,” said Tomasz Kardas, author of the software. “Experiments, which until now could not be simulated even by large laser centers, can now be designed — and after a certain time, probably also performed — by researchers from much smaller laboratories.” The latest version of the Hussar program makes it possible to design, for example, a device for time-resolved fluorescence. With the new version, such a system could be simulated, and even beams that cross at angles of 140 degrees could be modeled. “For some time now, we have been developing our own software that simulates without approximations what happens when femtosecond laser pulses overlap, naturally taking into account so-called nonlinear phenomena,” Kardas said. “Like others, we were limited to collinear beams for computational reasons.” Dr. Tomasz Kardas from the Laser Center of the Institute of Physical Chemistry of the Polish Academy of Sciences and the Faculty of Physics, University of Warsaw, in a festive way visualizes the beams of ultrashort laser pulses, simulated by Hussar software. Courtesy of IPC PAS, Grzegorz Krzyzewski. “Fortunately, we have recently been able to significantly improve the mathematical description and use a unidirectional approach for modeling of beams at their crossroads,” he said. “We have used the occasion to create some interesting tools such as a pulse electric field rotation algorithm that is 1000 times faster than the interpolation usually used for this purpose.” The new version of the software will enable the design of optical experiments that would previously have required an iterative approach. Hussar software could also help with large optical projects such as the design of noncollinear parametric amplifiers. There are equally interesting possibilities of using the software to model optical systems with three or more beams, the researchers said. The research was published in Scientific Reports (https://doi.org/10.1038/s41598-018-32676-9). With the Hussar program, you can now efficiently model the interactions of femtosecond laser pulses traveling at a mutual angle of up to 140 degrees. Courtesy of IPC PAS. “ With the Hussar program, you can now efficiently model the interactions of femtosecond laser pulses traveling at a mutual angle of up to 140 degrees. Courtesy of IPC PAS. “