This study presents a novel nanocomposite-superlattice structure for low-energy and high-stability nanoscale phase-change memory (PCM). The researchers developed a superlattice based on Ge₄Sb₆Te₇ (GST467), a new nanocomposite with higher crystallization and lower melting temperatures than traditional PCM materials. This material consists of epitaxial SbTe nanoclusters within a Ge-Sb-Te matrix, which act as a precursor for crystallization and enhance the switching speed of GST467. The resulting PCM devices achieve record-low power density of approximately 5 MW/cm² and a switching voltage of approximately 0.7 V, compatible with modern logic processors. These devices also exhibit low resistance drift with 8 resistance states, good endurance (approximately 2×10⁸ cycles), and fast switching (approximately 40 ns). The efficient switching is enabled by strong heat confinement within the superlattice materials and the nanoscale device dimensions. The microstructural properties of GST467 and its high crystallization temperature contribute to the fast-switching speed and stability of the superlattice PCM devices. These results re-establish PCM technology as a leading candidate for energy-efficient data storage and computing. The study also demonstrates the potential of GST467-based superlattice PCM devices for high-density, low-power applications, including embedded memory for automotive and IoT devices. The research highlights the importance of material design and engineering in achieving high-performance, energy-efficient PCM devices.This study presents a novel nanocomposite-superlattice structure for low-energy and high-stability nanoscale phase-change memory (PCM). The researchers developed a superlattice based on Ge₄Sb₆Te₇ (GST467), a new nanocomposite with higher crystallization and lower melting temperatures than traditional PCM materials. This material consists of epitaxial SbTe nanoclusters within a Ge-Sb-Te matrix, which act as a precursor for crystallization and enhance the switching speed of GST467. The resulting PCM devices achieve record-low power density of approximately 5 MW/cm² and a switching voltage of approximately 0.7 V, compatible with modern logic processors. These devices also exhibit low resistance drift with 8 resistance states, good endurance (approximately 2×10⁸ cycles), and fast switching (approximately 40 ns). The efficient switching is enabled by strong heat confinement within the superlattice materials and the nanoscale device dimensions. The microstructural properties of GST467 and its high crystallization temperature contribute to the fast-switching speed and stability of the superlattice PCM devices. These results re-establish PCM technology as a leading candidate for energy-efficient data storage and computing. The study also demonstrates the potential of GST467-based superlattice PCM devices for high-density, low-power applications, including embedded memory for automotive and IoT devices. The research highlights the importance of material design and engineering in achieving high-performance, energy-efficient PCM devices.