Modification of relaxation dynamics in Tb3+:Y3Al5O12 nanopowders

Abstract

Nanostructured rare-earth-ion doped materials are increasingly being investigated for on-chip implementations of quantum information processing protocols as well as commercial applications such as fluorescent lighting. However, achieving high-quality and optimized materials at the nanoscale is still challenging. Here we present a detailed study into the restriction of phonon processes in the transition from bulk crystals to small (≤ 40 nm) nanocrystals by observing the relaxation dynamics between crystal-field levels of Tb 3+ :Y3Al5O12. We find that population relaxation dynamics are modified as the particle size is reduced, consistent with our simulations of inhibited relaxation through a modified vibrational density of states and hence modified phonon emission. However, our experiments also indicate that non-radiative processes not driven by phonons are also present in the smaller particles, causing transitions and rapid thermalization between the levels on a timescale of < 100 ns.

Effects of fabrication methods on spin relaxation and crystallite quality in Tm-doped Y3Al5O12 powders studied using spectral hole burning

“…In contrast to REI doped bulk materials, powders offer low cost and rapid prototyping. Furthermore, the understanding of powders constitutes a first step towards nanofabrication of devices from these materials [4][5][6][7]. However, despite much effort [8][9][10][11], producing monodisperse powders with properties comparable to those of bulk materials remains challenging.…”

Controlled size reduction of rare earth doped nanoparticles for optical quantum technologies

“…Very high quality materials are therefore needed to reach T 2 values comparable to bulk samples. In this sense, Eu 3+ doped Y 2 O 3 is a particularly interesting candidate: in contrast to other RE materials, 27,[32][33][34] Eu 3+ doped Y 2 O 3 nanoparticles presenting remarkable optical and spin coherence properties, as well as narrow size distribution and bulk-like optical absorption and emission features can be obtained by chemical synthesis. [35][36][37] Our previous studies on Eu 3+ :Y 2 O 3 nanoparticles synthesized by homogeneous precipitation demonstrated an optical homogeneous linewidth of 45 kHz (T 2 ¼ 7 ms) for the Eu 3+ : 7 F 0 / 5 D 0 transition at 580 nm in 400 nm-diameter particles.…”

Recent Advances in Rare Earth Doped Inorganic Crystalline Materials for Quantum Information Processing

“…In contrast, annealing at high temperatures can improve the coherence properties and reduce the linewidths again to values less than 10 kHz, which is close to the bulk single crystal linewidth. In a further study on Tm 3+ ‐doped Y 3 Al 5 O 12 it was also found that mechanical treatment degrades the coherence properties of a material, whereas thermal annealing can improve them.…”