Studies of top quark properties in ATLAS

Due to its high mass top quarks decay before top-flavoured hadrons can be formed. This feature yields experimental access to the top quark polarization and production asymmetries. The large top quark sample moreover enables measurements of other properties, such as the W-boson branching ratios and helicity, and fragmentation functions of the bottom quarks. In this contribution, recent measurements of top quark properties are presented, including in particular a first analysis of the energy asymmetry in ttbar production and a measurement of top-quark polarization in single-top quark production.