Hoi-Kwong Lo wins international scientific award from Optica
He receives the 2026 Leonard Mandel Quantum Optics Award from the society dedicated to the science of light
CQT Principal Investigator Hoi-Kwong Lo is the 2026 recipient of an international prize for “distinguished contributions to the foundations of statistical and quantum optics, and/or applications in advanced technologies”.
He has won the Leonard Mandel Quantum Optics Award presented by Optica, a society dedicating to advancing optics and photonics worldwide that was founded in 1916. It is one of 22 awards announced by Optica on 19 February 2026.
Hoi-Kwong, who has a joint appointment as Provost’s Chair Professor in the National University of Singapore’s Department of Physics, is recognised for contributions including the invention of decoy-state and measurement-device-independent quantum key distribution (QKD) and the all-photonic quantum repeater.
“I am deeply honoured by the award. Frankly, when I started working in quantum information decades ago, I did it for fun and for intellectual curiosity. I had no idea that quantum information would become a mainstream and hot research topic today,” says Hoi-Kwong. “I hope that my research work will be widely used in society in the future and will benefit the world in some way.”
Lighting the way
Hoi-Kwong has worked extensively on the theory and implementation of QKD.
In general, QKD protocols use the quantum properties of light particles to create and share encryption keys for secure communication. The technology’s promise to resist computational hacks is driving trials in many countries – including in Singapore. For example, four banks collaborated with the Monetary Authority of Singapore in 2025 to complete a proof-of-concept sandbox to evaluate the use of QKD in the financial sector.
QKD protocols however differ in many details of how photons are made and measured. Hoi-Kwong contributed to inventing protocols that counter potential weaknesses in practical implementations of QKD. He was a pioneer of the now widely-used decoy-state protocols, which deploy variations in the intensity of transmission to help reveal eavesdroppers, and he invented measurement-device-independent QKD to remove potential detector side channel attacks.
Hoi-Kwong is also co-founder of the start-up Quantum Bridge, which works on quantum-safe communication and quantum repeaters. Large quantum networks will need repeaters to make up for photons lost to absorption over long-distance travel. Where researchers previously expected to need some kind of solid-state or cold atom interface, Hoi-Kwong came up with an all-photonic approach.
Third to win
The Leonard Mandel Quantum Optics Award was established in 2023, making Hoi-Kwong only the third recipient after H. Jeff Kimble in 2024 and James D Franson in 2025. It is named for the experimental physicist Leonard Mandel (1927-2001) who did groundbreaking work in quantum optics, including making the first observation of photon anti-bunching and introducing the Hong-Ou-Mandel interferometer named for him among others.
Optica, which has its headquarters in Washington DC in the United States, has members around the world. Hoi-Kwong was first elected an Optica Fellow in 2019 when he was based at the University of Toronto in Canada.
Reflecting on his new achievement, Hoi-Kwong says “I would like to take this opportunity to thank my mentors, collaborators, postdocs, and students from the bottom of my heart. Without their selfless and invaluable contributions, this award would not have been possible.”
