Extreme loss suppression in an ultracold molecular gas with widely tunable dipolar interactions.

Double-microwave dressing suppresses inelastic losses in ultracold KRb molecules by over 10,000-fold, enabling stable quantum gases with tunable dipolar interactions.

• Why it matters: Achieving long-lived, strongly interacting dipolar molecular gases is essential for exploring exotic quantum states, but inelastic collisions have historically limited their stability and utility.
• What they did: Researchers used double-microwave dressing to create a collisionally stable ultracold molecular gas with a lifetime of several seconds, suppressing two- and three-body losses across a wide dipolar interaction range.
• The result: This breakthrough allows continuous tuning of dipolar length from -21,000 to 12,000 a₀, paving the way for studying strongly dipolar quantum liquids and advancing quantum many-body physics.