Topological defects coupling smectic modulations to intra-unit-cell nematicity in cuprates

Area of Science:

• Condensed Matter Physics
• Materials Science
• Quantum Materials

Background:

• Underdoped cuprates exhibit complex electronic phases, including pseudogap states.
• Coexistence of smectic modulations and intra-unit-cell nematicity is observed in these materials.
• Understanding these coexisting orders is crucial for elucidating high-temperature superconductivity mechanisms.

Purpose of the Study:

• To investigate the relationship between smectic modulations and intra-unit-cell nematicity in Bi(2)Sr(2)CaCu(2)O(8+δ).
• To identify the underlying physical mechanisms driving the interplay between these two electronic orders.
• To develop a theoretical framework explaining their coexistence and atomic-scale interactions.

Main Methods:

• Visualization of spatial components of smectic modulations and intra-unit-cell nematicity.
• Identification and mapping of 2π topological defects within smectic states.
• Simultaneous imaging of topological defects and nematicity fluctuations.

Main Results:

• 2π topological defects were identified throughout the phase-fluctuating smectic states.
• Strong empirical evidence for coupling between topological defects and intra-unit-cell nematicity was observed.
• A Ginzburg-Landau functional was proposed and validated, explaining the coexistence and interplay of symmetries.

Conclusions:

• The proposed Ginzburg-Landau functional successfully describes the coupling between smectic and nematic orders.
• This theoretical framework provides insights into the atomic-scale interplay of broken symmetries in cuprates.
• The findings contribute to unraveling the complex phase diagram of high-critical-temperature superconductors.