  Efficient verification of quantum states and gates is crucial to the
development of quantum technologies. Although the sample complexities of
quantum state verification and quantum gate verification have been studied by
many researchers, the number of experimental settings has received little
attention and is poorly understood. In this work we study systematically
quantum state verification and quantum gate verification with a focus on the
number of experimental settings. We show that any bipartite pure state can be
verified by only two measurement settings based on local projective
measurements. Any bipartite unitary in dimension $d$ can be verified by $2d$
experimental settings based on local operations. In addition, we introduce the
concept of entanglement-free verification and clarify its connection with
minimal-setting verification. Finally, we show that any two-qubit unitary can
be verified with at most five experimental settings; moreover, a generic
two-qubit unitary (except for a set of measure zero) can be verified by an
entanglement-free protocol based on four settings. In the course of study we
clarify the properties of Schmidt coefficients of two-qubit unitaries, which
are of independent interest.
