Combining In-situ Uniaxial Strain and Single Crystal X-ray Scattering to Study Condensed Matter Challenges from Nematicity to Bicritical Behavior.

In this talk I will review how deploying single crystal in-situ uniaxial strain using low temperature x-ray scattering with simultaneous electrical measurement capabilities at the Advanced Photon Source deepens our understanding of complex quantum phenomena. X-ray techniques including high resolution diffraction, resonant magnetic, linear / circular and inelastic scattering have facilitated the exploration of fundamental characteristics within material systems displaying emergent quantum behaviors. 

 

To illustrate this ongoing instrument development we will discuss i) nematic behavior in Fe based superconductors (1,-3) and ii) the bicritical behavior in rare earth(RE) tri-tellurides. (4) Here, electronic or structural nematicity is coupled to both the lattice and conducting electrons making structural and transport measurements sensitive to the underlying fluctuations. This, in principle makes x-ray scattering coupled with electrical measurements indispensable tools in this field. In the RE tri-tellurides, structural instabilities in the form of charge density waves (CDW) emerge. Uniaxial strain materializes as a key mechanism for controlling the orientation of these modulations The coexistence of orthogonal CDWs further creates a strain-variable bicritical phase space, offering a rich terrain for investigation and discovery. Lastly, we will provide insights into our ongoing studies in strain-based quantum devices (5) and offer a glimpse into our future plans, which encompass multi-modal instrument developments harnessing the power of combined x-ray techniques.