We show that two identical solid-state qubits can be made fully entangled
(starting from completely mixed state) with probability 1/4 just measuring them
by a detector, equally coupled to the qubits. This happens in the case of
repeated strong (projective) measurements as well as in a more realistic case
of weak continuous measurement. In the latter case the entangled state can be
identified by a flat spectrum of the detector shot noise, while the
non-entangled state (probability 3/4) leads to a spectral peak at the Rabi
frequency with the maximum peak-to-pedestal ratio of 32/3.Comment: 5 pages, 2 figure