Characterization ofYb3+171:YVO4for photonic quantum technologies

Abstract

Rare-earth ions in crystals are a proven solid-state platform for quantum technologies in the ensemble regime and attractive for new opportunities at the single ion level. Among the trivalent rare earths, 171 Yb 3+ is unique in that it possesses a single 4f excited-state manifold and is the only paramagnetic isotope with a nuclear spin of 1/2. In this work, we present measurements of the optical and spin properties of 171 Yb 3+ :YVO 4 to assess whether this distinct energy level structure can be harnessed for quantum interfaces. The material was found to possess large optical absorption compared to other rare-earth-doped crystals owing to the combination of narrow inhomogeneous broadening and a large transition oscillator strength. In moderate magnetic fields, we measure optical linewidths less than 3 kHz and nuclear spin linewidths less than 50 Hz. We characterize the excited-state hyperfine and Zeeman interactions in this system, which enables the engineering of a Λ-system and demonstration of all-optical coherent control over the nuclear spin ensemble. Given these properties, 171 Yb 3+ :YVO 4 has significant potential for building quantum interfaces such as ensemble-based memories, microwave-to-optical transducers, and optically addressable single rareearth-ion spin qubits.

Control and single-shot readout of an ion embedded in a nanophotonic cavity

“…While the source of the optical dephasing is still under investigation, it will likely be improved in higher purity samples (See SI 6.5). While not explored here, the high magnetic field regime offers the possibility of longer optical and spin coherence times at the expense of weaker spin transition strengths (15). : YVO.…”

Characterization of the Superhyperfine Interaction in 171Yb:YVO4

“…We applied perturbation theory on our energy eigenstates to obtain the transition sensitivity ∂ ω ∂ B and simulated spin flips of the neighboring atoms to estimate the B field fluctuations. Using these parameters, we estimated the resultant coherence times [4,5] and compared against photon-echo and spin-echo decay measurements from two-pulse echo experiments [3]. Figs 3a and 3b show a close correspondence of both the qualitative trend and numerical values between the predictions and experimental results.…”

“…In particular, 171 Yb 3+ ions are attractive because their electronic and nuclear spins of 1 /2 allow for coupling to both optical and microwave photons while maintaining a simple energy level structure. In addition, their coherence properties have recently been studied and show promise for quantum memories and optically addressable single rare-earth-ion qubits [3]. One important aspect of such systems is the superhyperfine interaction between the rare-earth ion and host nuclei, which could be used to address the host nuclear spins to store quantum information in long-lived superhyperfine states, but at the same time is a significant contribution to decoherence of the optical and spin transitions at cryogenic temperatures [2].…”

Toward Coherent Control of Single Yb3+ Ions in a Nanophotonic Cavity

“…This gives rise to a simple level structure that allows efficient microwave manipulation of the electron spin and long term storage on the nuclear spin. Furthermore, recent spectroscopy of 171 Yb 3+ doped in YVO 4 shows that the optical and spin properties of this material are promising for nanoscale quantum interfaces [4]. In this work, we report progress on detection and manipulation of single Yb 3+ ions coupled to nanophotonic cavities fabricated in the YVO 4 crystal host.…”