Lindhard

Lindhard is a surname of Danish origin. In science, it is most prominently associated with Jens Lindhard, a Danish physicist whose work in the mid-20th century produced foundational theories and tools for condensed matter and nuclear physics. One widely cited concept is the Lindhard function, the density–density response function of a uniform free electron gas. It describes how the electron sea responds to external perturbations and forms the basis of many calculations of electronic screening and collective excitations.

Another key contribution is the Lindhard theory of electronic stopping power, which describes how energetic ions lose energy to electrons in a solid. This theory helps model radiation damage, ion implantation, and detector responses in materials.

In detector physics, the Lindhard factor (often called the Lindhard quenching factor) expresses the fraction of recoil energy that goes into detectable electronic excitations, as opposed to lattice vibrations. This quantity is important in direct detection experiments for dark matter and other rare-event searches.

Beyond these, the Lindhard name appears in various related models and formulae in solid-state and plasma physics. The surname remains associated with foundational theoretical developments in describing how charged particles interact with matter.