A quantum interferometer can achieve phase sensitivity beyond the classical limit by using the nonclassical properties of the quantum state. The SU(1,1) interferometer, a commonly used quantum interferometer, can be realized by replacing the linear beam splitters in a Mach-Zehnder interferometer with nonlinear processes. The phase sensitivity of the SU(1,1) interferometer increases with an increase of internal photon number. Therefore, the bright-seeded SU(1,1) interferometer has an advantage of boosted sensitivity. However, the phase sensitivity of a bright-seeded SU(1,1) interferometer is usually susceptible to unavoidable optical losses in experiments, especially the internal losses, which limit its applications. Here, we propose a loss-resistant bright-seeded SU(1,1) quantum interferometer based on joint detection, in which intensity detection is implemented by subtracting part of the probe beam from the conjugate beam. We introduce a tunable parameter $t$ in this intensity detection and obtain the optimal $t$ as a function of internal losses. Such a scheme allows for better phase sensitivity in the presence of optical losses. Our results provide an alternate method for realizing a loss-resistant SU(1,1) interferometer and may promote the applications of the SU(1,1) interferometer in practical quantum measurements.

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• Optical interferometry
• Quantum metrology
• Nonclassical interferometry