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Quantum sources that provide broadband biphotons entangled in both polarization and time-energy degrees of freedom are a rich quantum resource that finds many applications in quantum communication, sensing, and metrology. Creating such a source while maintaining high entanglement quality over a broad spectral range is a challenge, which conventionally requires various compensation steps to erase temporal, spectral, or spatial distinguishabilities. Here, we point out that in fact compensation is not always necessary. The key to generate broadband polarization-entangled biphotons via type-II spontaneous parametric downcoversion (SPDC) without compensation is to use nonlinear materials with sufficiently low group birefringence that the biphoton bandwidth becomes dispersion-limited. Most nonlinear crystals or waveguides cannot meet this condition, but it is easily met in fiber-based systems. We reveal …