Stefan Junk


I'm a postdoc in Probability Theory at Kyoto University, where I am supported by JSPS as an International Research Fellow. I am hosted by David Croydon (Kyoto University) and Ryoki Fukushima (Tsukuba University).


I have written my PhD thesis about "random polymers in disastrous environments" with Nina Gantert at TU Munich.

Research interests

I'm mainly working on the following topics:
  • The directed polymer model, and first/last passage percolation.
  • (Branching) random walks in random environment.
  • Stochastic orders, in particular for the above processes.
  • Oriented percolation.
  • The random conductance model, and the Mott random walk in particular.
More broadly, I'm interested in the following areas:
  • Statistical mechanics.
  • Random matrices and integrable probability.
  • Large deviation theory.
  • Random walks on graphs and their resistane forms.

Paper and preprints

  • On large deviation rate functions for a continuous-time directed polymer in weak disorder, with Ryoki Fukushima. (arXiv).
  • Comparison of partition functions in a space-time random environment. Journal of Statistical Physics, 2020. (Journal, arXiv).
  • Zero temperature limit for the Brownian directed polymer among Poissonian disasters, with Ryoki Fukushima. Annals of Applied Probability, 2019. (Journal, arXiv)
  • A branching random walk among disasters, with Nina Gantert. Electronic Journal of Probability, 2017. (Journal, arXiv)
  • On the survival probability of a random walk in random environment with killing. ALEA Latin American Journal of Probability and Mathematical Statistics, 2014. (Journal, arXiv)

Teaching Experience

I have been TA for various courses as a PhD student in Munich, see here for a list.


Mail: Research Institute for Mathematical Sciences, Kyoto University, Kyoto 606-8502, Japan (Access)