Jonathan Kollmer
Former Postdoc
- Email: jekollme@ncsu.edu
- Office: 252 Riddick
Jonathan Kollmer is a postdoctoral research scholar at NC State University. He graduated with a physics diploma from the University of Bayreuth, Germany in 2009. He received his doctorate in 2015 from Friedrich-Alexander-Universität Erlangen Nürnberg, Germany working on dynamic granular systems. He moved to North Carolina to join NC State in 2016. His current research involves force networks in static granular systems. He also has a strong research interest in granular systems under low gravity and has done microgravity experiments on multiple parabolic flights and the Bremen drop tower.
Update from May 2018: Find Jonathan back in Germany, doing more astrophysics-with-grains in Duisberg!
PeGS
Photoelastic Grain Solver (PeGS)
Jonathan is the author and maintainer of the PeGS open source project. PeGS is a tool to extract vectorial contact forces from images of photoelastic particles. PeGS is described in detail in the article “Photoelastcic force measurements in granular materials” and the source code is available on GitHub .
Publications
- Spongelike Rigid Structures in Frictional Granular Packings
- Liu, K., Kollmer, J. E., Daniels, K. E., Schwarz, J. M., & Henkes, S. (2021), Physical Review Letters, 126(7). https://doi.org/10.1103/PhysRevLett.126.088002
- Migrating Shear Bands in Shaken Granular Matter
- Kollmer, J. E., Shreve, T., Claussen, J., Gerth, S., Salamon, M., Uhlmann, N., … Poeschel, T. (2020), PHYSICAL REVIEW LETTERS, 125(4). https://doi.org/10.1103/PhysRevLett.125.048001
- Rigidity percolation control of the brittle-ductile transition in disordered networks
- Berthier, E., Kollmer, J. E., Henkes, S. E., Liu, K., Schwarz, J. M., & Daniels, K. E. (2019), Physical Review Materials, 3(7). https://doi.org/10.1103/PhysRevMaterials.3.075602
- Photoelastic force measurements in granular materials
- Daniels, K. E., Kollmer, J. E., & Puckett, J. G. (2017), REVIEW OF SCIENTIFIC INSTRUMENTS, 88(5). https://doi.org/10.1063/1.4983049
