This study presents a high-performance quantum-dot (QD) laser grown directly on silicon (Si) that achieves self-injection locking (SIL) coherence under turnkey external cavity locking (ECL). The QD laser offers a scalable and low-cost heteroepitaxial integration platform, enabling narrow linewidths and high coherence. The QD laser's chaos-free nature allows for a 16 Hz Lorentzian linewidth under ECL using a low-Q external cavity, and improves frequency noise by an additional order of magnitude compared to conventional quantum-well (QW) lasers. Narrow-linewidth and frequency-stable lasers are crucial for applications such as optical sensing, signal generation, and coherent optical communications. The QD laser's low linewidth enhancement factor (LEF) and high immunity to defects make it suitable for monolithic integration on Si substrates. The QD laser's performance is further enhanced by its compatibility with high-Q microresonators, enabling further linewidth reduction. The study demonstrates that the QD laser can achieve a 16 Hz linewidth without a high-Q external cavity, offering a turnkey solution with no power penalty. The QD laser's performance is compared to conventional QW lasers, showing significant improvements in linewidth and frequency noise. The study also highlights the potential of QD lasers in applications requiring precise coherence, particularly where achieving ultra-high-Q resonators is challenging. The QD laser's turnkey operation and power-maintaining characteristics make it suitable for high-temperature applications. The study concludes that the QD laser is a compelling candidate for various high-coherence applications, including optical frequency synthesizers, dual-comb spectroscopy, and ultra-high-capacity optical transceivers.This study presents a high-performance quantum-dot (QD) laser grown directly on silicon (Si) that achieves self-injection locking (SIL) coherence under turnkey external cavity locking (ECL). The QD laser offers a scalable and low-cost heteroepitaxial integration platform, enabling narrow linewidths and high coherence. The QD laser's chaos-free nature allows for a 16 Hz Lorentzian linewidth under ECL using a low-Q external cavity, and improves frequency noise by an additional order of magnitude compared to conventional quantum-well (QW) lasers. Narrow-linewidth and frequency-stable lasers are crucial for applications such as optical sensing, signal generation, and coherent optical communications. The QD laser's low linewidth enhancement factor (LEF) and high immunity to defects make it suitable for monolithic integration on Si substrates. The QD laser's performance is further enhanced by its compatibility with high-Q microresonators, enabling further linewidth reduction. The study demonstrates that the QD laser can achieve a 16 Hz linewidth without a high-Q external cavity, offering a turnkey solution with no power penalty. The QD laser's performance is compared to conventional QW lasers, showing significant improvements in linewidth and frequency noise. The study also highlights the potential of QD lasers in applications requiring precise coherence, particularly where achieving ultra-high-Q resonators is challenging. The QD laser's turnkey operation and power-maintaining characteristics make it suitable for high-temperature applications. The study concludes that the QD laser is a compelling candidate for various high-coherence applications, including optical frequency synthesizers, dual-comb spectroscopy, and ultra-high-capacity optical transceivers.