  We present a renormalization group treatment of quantum tricriticality in
metals. Applying a set of flow equations derived within the functional
renormalization group framework we evaluate the correlation length in the
quantum critical region of the phase diagram, extending into finite
temperatures above the quantum critical or tricritical point. We calculate the
finite temperature phase boundaries and analyze the crossover behavior when the
system is tuned between quantum criticality and quantum tricriticality.
