Origin, Symmetry and Elastic Tuneability of Charge Density Waves in the Superconductor BaNi₂(As₁₋ₓPₓ)₂

This book plays a crucial role in unveiling the complex interplay between incommensurate and commensurate CDWs and superconductivity in these systems. Charge density waves (CDWs) are a fascinating electronic order observed in numerous quantum materials, often in close proximity to superconducting phases. Their significance has only grown since their discovery in cuprate superconductors and, more recently, in kagome superconductors. Mr. Lacmann’s Ph.D. research has made groundbreaking contributions to this field by investigating materials derived from BaNi₂As₂—a non-magnetic analogue of the parent compounds of iron-based superconductors. This book presents an impressive array of synchrotron-based experimental results, shedding light on (i) the unconventional nature and origin of CDWs in BaNi₂(As₁₋ₓPₓ)₂, (ii) their symmetry, and (iii) the influence of hydrostatic and uniaxial pressure on these electronic phases. The innovative methodologies have been widely adopted, significantly impacting the field. With nine co-authored publications—including two in nature communications and two in physical review letters—and two more in advanced preparation, his contributions are truly exceptional. Mr. Lacmann’s outstanding achievements and lasting impact make him highly deserving of this award.