Moving closer to ground state physics
Moving closer to ground state physics lead image
Resonant soft X-ray scattering (RSXS) is a powerful tool for probing complex materials, capable of revealing emerging functionalities such as ferromagnetism, multiferroicity, superconductivity, and two-dimensional topological properties. Through resonant effects, it also characterizes electronic structures.
Launched in 2015, the first RSXS endstation at the Stanford Synchrotron Radiation Lightsource (SSRL) has enabled many successful research efforts, but its base temperature remained at 23.5 K, hindering exploration of hidden quantum phenomena below this temperature.
To overcome this limitation, Kuo et al. designed a novel RSXS setup at SSRL. They achieved a base temperature of 9.8 K by minimizing thermal loss and expanding angular motion in two degrees of freedom with additional in-vacuum motors.
“The new RSXS system greatly enhances reciprocal space coverage, angular precision, and access to low-temperature physics,” said author Cheng-Tai Kuo. “This enables investigations into the subtle interplay between charge density waves and superconductivity in regimes previously inaccessible due to thermal or geometric limitations.”
Further photon scattering experiments demonstrated the system’s effectiveness in probing complex materials, such as superlattice heterostructures and high-temperature superconductors, near the ground state.
In the future, the authors plan to further enhance the probing capability of RSXS toward quantum matter — including exotic magnetic systems and strongly correlated electron states.
“Looking ahead, we aim to integrate extreme sample environments into the RSXS platform. One promising direction is to introduce high magnetic fields, which can dramatically influence charge ordering and other emergent phenomena in superconductors,” said Kuo. “Another exciting avenue is the development of ultrafast RSXS techniques, enabling time-resolved studies of quantum phase dynamics. These advancements will further push the boundaries of how we probe, understand, and manipulate quantum matter.”
Source: “Introducing new resonant soft x-ray scattering capability in SSRL,” by Cheng-Tai Kuo, Makoto Hashimoto, Heemin Lee, Tan Thanh Huynh, Abraham Maciel, Zina Zhang, Dehong Zhang, Benjamin Edwards, Farzan Kazemifar, Chi-Chang Kao, Donghui Lu, and Jun-Sik Lee, Review of Scientific Instruments (2025). The article can be accessed at https://doi.org/10.1063/5.0257317 .
