Observation of the second proton alignment in $^{160}$Tm

High-spin states in the doubly odd nucleus 160Tm have been investigated using the $^{130}$Te($^{35}$Cl,5n) reaction and the Euroball $\gamma$-ray detector array. The previously established rotational structures in $^{160}$Tm were extended, leading to the first observation of the second (h$_{11/2})^2$ proton band crossing in this nucleus. This crossing is found to occur at a higher rotational frequency in $^{160}$Tm than in lighter Tm isotopes. This trend resembles that of the first (h$_{11/2})^2$ proton band crossing found in neighboring Er nuclei and is associated with a predicted increase in deformation as a function of neutron number in these isotopes