Introduction
Quantum Science and Technology (QST) is an emerging research and education frontier that has generated a great deal of interests and stimulated novel potential applications for the last decade. The aim of the 2021 workshop on QST is to bring together researchers in this area to present their recent findings, and to promote and enhance research activities, interactions and collaborations among the participants. The workshop will cover all related subjects in QST, and the invited speakers will include both theorists and experimentalists.