  We show that it is possible to employ reservoir engineering to turn two
distant and relatively bad cavities into one good cavity with a tunable
spontaneous decay rate. As a result, quantum computing schemes, that would
otherwise require the shuttling of atomic qubits in and out of an optical
resonator, can now be applied to distant quantum dots. To illustrate this we
transform a recent proposal to entangle two qubits via the observation of
macroscopic fluorescence signals [Metz et al., Phys. Rev. Lett. 97, 040503
(2006)] to the electron-spin states of two semiconductor quantum dots. Our
scheme requires neither the coherent control of qubit-qubit interactions nor
the detection of single photons. Moreover, the scheme is relatively robust
against spin-bath couplings, parameter fluctuations, and the spontaneous
emission of photons.
