Researchers at NIST have developed a new method for precisely controlling and measuring the quantum states of single trapped molecular ions using co-trapped atomic ions. The technique, called quantum logic spectroscopy, allows them to prepare, control, and measure the complex quantum states of molecules by transferring information between the molecular ions and atomic ions.
The process involves cooling the atomic ions to their lowest energy state, then using laser light to excite specific quantum states in the molecular ions. The information about the molecular states is transferred to the atomic ions, which can then be measured using fluorescence detection. This method has enabled researchers to prepare and detect molecular ions in pure quantum states, as well as entangle molecular and atomic ions.
The new technique requires only two lasers to manipulate the molecular states, spanning a wide range of frequencies from radio to optical. This makes it applicable to a broad range of molecular species. However, the researchers have identified background blackbody radiation as a limiting factor, and are currently working on a new cryogenic setup to improve vacuum and reduce radiation intensity.
The potential applications of this technology include quantum information processing, precision spectroscopy, and fundamental physics research. By controlling molecular states, researchers hope to unlock new functionalities in quantum computing platforms, improve sensitivity in fundamental physics experiments, and contribute to quantum control of chemical reactions.
Keywords: Rovibrational, Quantum-state, Coherent, Spectroscopy, Quantum control
