Spectroscopic evidence of cooperative (entangled) quantum states of Nd3+ ion pairs in Nd3+: LaF3 crystal

Local Structure of the Impurity Site in Nd:LaF3 by X‐Ray Fluorescence Holography

“…[ 14,18 ] Furthermore, Nd:LaF 3 is of interest for spectrocopic investigations, e.g., concerning cooperative quantum states of Nd ion pairs. [ 19,20 ] To understand the remarkable properties of Nd:LaF 3 , it is important to clarify the position of the dopant in the host lattice and the extent of local lattice distortions around it.…”

Rare earth ions doped mixed crystals for fast quantum computers with optical frequency qubits

“…In the case of Kramers REI's with half-integer spin, the strongest spin-spin interaction at short distances is the exchange interaction J [50,51]. For example, for nearest pair centers of 3 Nd  this interaction is of the order of several cm -1 , and it is responsible for the singlet-triplet splitting 2 2 5 J  cm -1 of the ground state [50][51][52]. With increasing distance, this interaction decreases exponentially, and for 3 Ra  it can be neglected.…”

“…In this case one usually speaks of pair, triple, etc. centers [51,52,55]. In the case under consideration (   ), the number of such centers is low.…”