Extending Phenomenological Crystal-Field Methods to C1 Point-Group Symmetry: Characterization of the Optically Excited Hyperfine Structure of Er

Abstract

We show that crystal-field calculations for C1 point-group symmetry are possible, and that such calculations can be performed with sufficient accuracy to have substantial utility for rare-earth based quantum information applications. In particular, we perform crystal-field fitting for a C1-symmetry site in 167 Er 3+ :Y2SiO5. The calculation simultaneously includes site-selective spectroscopic data up to 20,000 cm −1 , rotational Zeeman data, and ground-and excited-state hyperfine structure determined from high-resolution Raman-heterodyne spectroscopy on the 1.5 µm telecom transition. We achieve an agreement of better than 50 MHz for assigned hyperfine transitions. The success of this analysis opens the possibility of systematically evaluating the coherence properties, as well as transition energies and intensities, of any rare-earth ion doped into Y2SiO5.

Prediction of optical polarization and high-field hyperfine structure via a parametrized crystal-field model for low-symmetry centers in Er3+ -doped Y2SiOJobbitt1, Wells2, Reid3 et al. 2021Phys. Rev. BSelf Cite13150View full textAdd to dashboardCite

“…S and I are vector representations of the electronic and nuclear spin operators respectively. Rather than fit to the tensors, in our fits we evaluate Hamiltonian (1) at various magnetic field directions [16]. This results in a separate Hamiltonian matrix for each set of data, evaluated at a particular magnetic field sampled from the parametric spiral:…”

“…Trivalent erbium is of particular interest for quantum information applications as the ion possesses optical transitions in the well established 1.5 µm telecommunications band, the narrowest optical homogeneous linewidth observed to date (50 Hz) [15], in addition to a spin coherence time of over one second [5]. Furthermore, Er 3+ has a large hyperfine splitting relative to Pr 3+ and Eu 3+ [4,13,16] which allows for larger memory bandwidths within these hyperfine transitions while still obtaining reasonably long coherence times.…”

“…Recently, crystal-field analyses have been performed for the C 1 symmetry centers in Ce 3+ , Er 3+ and Yb 3+ doped Y 2 SiO 5 [16][17][18][19]; with further analyses under way for Y 2 SiO 5 doped with Nd 3+ , Sm 3+ and Ho 3+ [20][21][22].…”

“…We report on infrared to visible Zeeman absorption spectroscopy for both Er 3+ centers in Y 2 SiO 5 , the data from which culminates in a parametrized crystal-field model accounting for the energy level structure up to 27 000 cm −1 , approximately seventy electronic g values measured along all three crystallographic axes as well as electron-paramagnetic resonance and Raman-heterodyne measurements obtained from the literature [16,[23][24][25]. The directional data provided by our Zeeman measurements over tens of electronic levels, allows us to obtain a well determined, unique set of crystal-field parameters and therefore goes well beyond what has been reported previously.…”

Измерения зеемановско-сверхтонкого псевдовырожденного квадруплета в CaF-=SUB=-2-=/SUB=-:Ho-=SUP=-3+-=/SUP=-

“…Такие переходы обычно связаны с антипересечениями (несостоявшимися пересечениями) сверхтонких подуровней. Отметим, недавно мы продемонстрировали, что можно выполнить расчеты по теории кристаллического поля для позиций с точечной группой симметрии C 1 в Y 2 SiO 5 [5] и использовать их предсказательную способность для интерпретации спектров со сверхтонкой структурой [6].…”