Professor Klaus Mølmer on Quantum Optics & The Thrill of Being the ‘Master of the Universe’

Insider Brief

• Professor Klaus Mølmer, a leading quantum optics researcher, underlined the field’s significance in understanding light-matter interactions and its fundamental role in quantum physics during a lecture at QuTalent.
• Mølmer highlighted the probabilistic nature of quantum optics, allowing exploration of individual particles and advancing quantum information technologies, particularly in secure communication.
• He shared his experiences in the lab, showcasing the profound impact of quantum optics on both research and future technological developments.

Professor Klaus Mølmer, a Danish physicist currently at the Niels Bohr Institute of the University of Copenhagen and one of the most eminent researchers in quantum optics, recently gave a lecture as part of QuTalent —  a talent development effort under the Singapore National Quantum Computing Hub (NQCH) — on his findings regarding the importance and potential for research in the area. For Mølmer, quantum optics is not a subfield of physics; rather, it represents an inseparable link to the most fundamental light-matter interaction.

“Quantum optics deals with the interaction of light and matter, but in a very special way,” Mølmer explained as a taster, which set us up for the microscopic world where the behavior of single atoms and photons can be observed and controlled. He underlined the unique challenges and opportunities this field presents, saying that while quantum optics might seem like a niche area, it is, in fact, “the heart of finding the quanta in the light.”

One of the most interesting aspects of quantum optics, according to Mølmer, is its probabilistic nature. 

“In quantum physics, the description is a probabilistic one. Things are not given with certainty; they’re given with probabilities,” he said. This fundamental principle allows researchers to explore the behavior of individual particles, pushing the boundaries of our understanding of the universe.

Mølmer shared a personal anecdote that vividly illustrated the power of quantum optics. He recalled a visit to an ion trap laboratory, where he witnessed the light emitted by a single atom: “In the dark of the lab, you can actually with your naked eyes see the light from one single atom. I felt a little bit like the master of the universe,” he said, capturing the awe and wonder that drives research in this field.

The implications of quantum optics extend far beyond the lab. Mølmer pointed out that the control over single photons and atoms has profound applications, particularly in quantum information technologies. 

“We are talking about using these light sources to send single photon by photon information,” he explained. This refers to quantum cryptography’s potential to revolutionize secure communication.

As quantum optics continues to evolve, it remains a cornerstone of cutting-edge research, driving advancements in quantum computing and beyond. Mølmer’s talk not only cleared up some of the problems with understanding this but also sends us a signal of the limitless possibilities that quantum optics holds for the future of science and technology.