A decades-old mystery in physics has been solved: the weird 'ghost' state of matter in superconductors is an independent traveler, not a precursor.
April 14, 2026
Original Paper
Ultrafast decoupling of the pseudogap from superconductivity in a pressurized cuprate
arXiv · 2604.10207
The Takeaway
Using high-pressure spectroscopy, researchers proved that the 'pseudogap' and superconductivity are two distinct phenomena that just happen to appear together. This allows scientists to stop trying to use one to explain the other, clearing the path to creating room-temperature superconductors.
From the abstract
The relationship between the pseudogap and superconductivity remains a central puzzle in the physics of cuprates. Hydrostatic pressure provides a clean tuning parameter free from chemical disorder, yet probing the microscopic energy scales of these phases under compression has remained experimentally challenging. Here, we utilize ultrafast optical spectroscopy to construct the high-pressure phase diagram of the underdoped cuprate Bi$_2$Sr$_2$CaCu$_2$O$_{8+\delta}$ up to 37 GPa. Our results revea