Researchers from Radboud University and Columbia University have developed an extremely stable quantum gas, offering a new avenue to study strongly interacting quantum systems. This gas is composed of molecular gases, a form of artificial quantum matter that can be manipulated in the lab. In traditional settings, these molecules often collide and are quickly lost, making it difficult to study their behavior. However, the researchers have found a way to suppress these losses, allowing for the creation of a more stable and controllable quantum system. Creating such a quantum gas requires cooling the molecules to temperatures just 0.000000001° above absolute zero, known as nanokelvin temperatures. At these extreme cold levels, quantum effects dominate, and the molecules behave collectively, forming a Bose-Einstein condensate. In this state, many molecules share the same quantum state, making it easier to study their interactions. This artificial quantum matter acts as a model system, allowing researchers to explore quantum behaviors similar to those found in real materials, but with greater control. A key challenge in working with ultracold molecules is the rapid collisional loss—when molecules collide, they often disappear from the system. To address this, researcher Tijn Karman and his team used microwaves to control the molecular dipole moments, effectively reducing the loss by more than 10,000 times. This breakthrough was achieved in the lab of Sebastian Will at Columbia University, where the suppression was so effective that the loss rate was limited only by the natural lifetime of a single molecule. By reducing collisional loss, the researchers were able to create denser and more stable molecular gases. Additionally, the microwave control induced strong, long-range interactions between the molecules. This combination allows for the creation of stable quantum liquids, where interactions between molecules extend beyond the average distance between them. Such systems offer a new platform to study strongly interacting quantum matter, which is challenging to achieve with atomic gases. Earlier, Karman also demonstrated the ability to create highly ordered molecular arrays, akin to molecules arranged in an egg carton, potentially serving as a foundation for using molecules as quantum bits in future quantum computing experiments. The findings have been published in the journal Science and are available on arXiv.