Ground-to-satellite and satellite-to-satellite quantum encrypted communications, distributed sensing, and networking demand a disruptive on-a-chip technology that permits ultra-efficient, high-speed entangled-photon generation and single-photon detection packaged to provide low size, weight, power, and cost. Building on the success of our Phase I program, this Phase II will develop and demonstrate a quantum photonics transceiver with plug-and-play modules comprising a time-bin entangled-photon pair generator, time-bin analyzers, and single-photon detector arrays, all operating at room temperature. The program integrates technology developed by the University of California, Santa Barbara, (UCSB) and Amethyst Research. The UCSB Team has demonstrated a <0.4 dB/cm loss AlGaAs-on-insulator photonics platform for entangled-photon pair generation. Signal rates >10 GHz/mW2 have been demonstratedat least 100X faster than all other approaches and 10,000X faster than silicon integrated-photonic sources. Waveguide-integrated superconducting single-photon detectors have also been demonstrated with sub-40 ps timing jitter, sub-milli-Hertz dark count rates, unity quantum efficiency, and -40 dB crosstalk. The Amethyst team has demonstrated InGaAs and GaSb based single-photon avalanche detectors (SPADs) capable of >100 MHz bandwidth at 250 K by using gating and proprietary bulk defect passivation techniques. By integrating these source and detector technologies, the program will deliver a high-speed quantum transceiver with an entangled-photon source and on-chip photonic conditioning components (transmitter) and photonic interferometric circuits with waveguide-integrated single-photon detectors (receiver). This on-a-chip quantum transceiver will be capable of uncompromised 'qubit' detection and demonstrate a time-bin entangled-pair QKD transceiver with plug-and-play receiver, transmitter, and detector modules at TRL 6. Potential NASA Applications (Limit 1500 characters, approximately 150 words) There is a need to develop large Low Earth Orbit (LEO) constellations that can deliver high-throughput broadband services with low latency. The development of a quantum photonic transceiver is vital to meet NASAs mission objectives for a scalable quantum network architecture, including distributed quantum sensing, improved timing, and secure communications. This program directly addresses the needs of the Deep Space Optical Communications program, which seeks to improve communications performance 10 to 100 times over state-of-the-art. Potential Non-NASA Applications (Limit 1500 characters, approximately 150 words) There is a pressing need for a low SWaP chip-scale quantum photonic transceiver that can provide robust and secure high-speed communications. Integrated quantum photonic devices may also find applications in quantum-enhanced distributed sensing, entanglement-based remote sensing with quantum frequency combs, LiDAR, optical interconnects for distributed quantum networks and the quantum internet.