We just finished a study demonstrating a way to use time-resolved RIXS to measure the collective exctiations of quantum materials, in this instance CDW-ordered La2-xBaxCuO4 (LBCO). The idea is to weakly perturb the system with a pump pulse and then measure the time evolution of the order parameter, which encodes the collective excitations of the […]
Our paper on density fluctuations in Bi2Sr2CaCu2O8+x appeared in the Proceedings of the National Academy of Sciences. This study shows that, unlike conventional metals, this so-called “strange metal” does not exhibit propagating plasmons. Instead, it shows a continuum of fluctuations exhibiting “local scale invariance”–a phase in which time and space axes become decoupled. The origin […]
We just published a paper finally demonstrating that TiSe2 contains a Bose condensate of excitons. The experimental signature is a soft plasmon that falls to zero frequency at Tc. Bert Halperin and Maurice Rice nicknamed this phase “excitonium” in their 1968 Rev. Mod. Phys. paper to emphasize the physical picture of an exciton condensate as an electronic crystal. […]
After 2.5 years of refereeing, Sean’s M-EELS paper was finally published in the open-access journal SciPost. This paper explains the reasons for developing the M-EELS technique and how it works. Read it here.
This joint paper spearheaded by Vidya Madhavan’s group shows the complementarity of M-EELS and scanning tunneling microscopy (STM) experiments. Read it here.
Anshul’s TiSe2Cux paper appeared in Phys. Rev. Lett.. This study shows that superconductivity in copper-doped materials is associated with an incommensurate phase, just as do materials subjected to hydrostatic pressure. Read it here.