Zeroing in on Zero-Point Motion Inside a Crystal
12 days ago
- #nanocrystals
- #zero-point motion
- #quantum physics
- Zero-point motion is quantum motion visible near absolute zero.
- Researchers identified a low-temperature emission effect in nanocrystals related to zero-point motion.
- Zero-point motion may help cool nanocrystals to lower temperatures than previously possible.
- Quantum fluctuations prevent motion from stopping completely, even at ultracold temperatures.
- Previous studies observed zero-point motion in trapped atoms, molecules, and mechanical resonators.
- New research detected zero-point motion within the lattice structure of a nanocrystal.
- Photoluminescence measurements revealed up-conversion, where emission frequency is higher than the laser's.
- Up-conversion removes energy from the object, potentially cooling it further.
- Lead-halide perovskite nanocrystals showed exciton emission even at 4 K, indicating zero-point motion.
- Zero-point motion creates an oscillating electric field, tilting the band structure and aiding electron transitions.
- This effect could enable cooling below 4 K, surpassing helium-based cryostat limits.
- The study offers a new approach to semiconductor optical refrigeration.
- Further thermodynamic measurements are needed to confirm cooling via zero-point up-conversion.