Narrow Optical Line Widths in Erbium Implanted in TiO₂

Abstract

Atomic and atom-like defects in the solid-state are widely explored for quantum computers, networks and sensors. Rare earth ions are an attractive class of atomic defects that feature narrow spin and optical transitions that are isolated from the host crystal, allowing incorporation into a wide range of materials. However, the realization of long electronic spin coherence times is hampered by magnetic noise from abundant nuclear spins in the most widely studied host crystals. Here, we demonstrate that Er 3+ ions can be introduced via ion implantation into TiO2, a host crystal that has not been studied extensively for rare earth ions and has a low natural abundance of nuclear spins. We observe efficient incorporation of the implanted Er 3+ into the Ti 4+ site (40% yield), and measure narrow inhomogeneous spin and optical linewidths (20 and 460 MHz, respectively) that are comparable to bulk-doped crystalline hosts for Er 3+ . This work demonstrates that ion implantation is a viable path to studying rare earth ions in new hosts, and is a significant step towards realizing individually addressed rare earth ions with long spin coherence times for quantum technologies. *

Multifunctional on-chip storage at telecommunication wavelength for quantum networks

“…Improvements to the intrinsic quality factor of the resonator are required to reach the impedance matching condition. Creative solutions such as using clock transitions in 167 Er 3+ :Y 2 SiO 5 [37,43,44], which are less sensitive to superhyperfine coupling, or finding new crystal hosts for erbium ions [45] can be used to overcome the superhyperfine limit.…”

Optical spin-state polarization in a binuclear europium complex towards molecule-based coherent light-spin interfaces

“…Optical qubit operations can be performed with systems featuring narrow linewidth optical transitions. Color centers in diamond 4 , rare-earth ions (REIs) doped in host matrices 2,[9][10][11][12][13] , and luminescent organic dye molecules (dye impurity), featuring extremely narrow and stable luminescent lines [14][15][16][17] , are suitable systems to implement optical qubit operations. REI-doped systems are particularly well-suited for optical QIP applications due to the following intrinsic properties.…”

Optical quantum nondemolition measurement of a single rare earth ion qubit

“…Longer coherence times to enable storage of quantum states and the observation of coherent dynamics between interacting Er 3+ ions may be achieved using dynamical decoupling. Ultimately, it will be beneficial to use alternative host crystals with lower nuclear spin content; Er 3+ incorporation has been demonstrated in several candidates including CaWO 4 , Si, and TiO 2 36 . Fig.…”