Erbium dopants - a novel platform for quantum network | Andreas Reiserer
▶ Title: Erbium dopants - a novel platform for quantum network
▶ Abstract:
In spite of decade-long research into different physical systems, the demonstration of a scalable platform for quantum networks and distributed quantum information processing remains an outstanding challenge. In this context, our group investigates the use of erbium dopants in silicon [1, 2] and silicate crystals [3-6]. This platform offers unique potential to overcome the main bottlenecks of other quantum hardware: First, erbium dopants can exhibit second-long coherence in a temperature range that is accessible with 4He cryocoolers [7]. Second, the optical transition of erbium is the narrowest spectral feature ever measured in a solid. Thus, frequency-multiplexed addressing of individual dopants [6, 8] gives access to an unprecedented qubit density as long as spin-spin interactions can be suppressed by dynamical decoupling [5]. Finally, by embedding the dopants into a cryogenic Fabry-Perot resonator with a quality factor of 107, we could demonstrate up to 70-fold Purcell enhancement with lifetime-limited optical coherence in the telecommunications frequency window [3]. In recent experiments, we could observe and coherently control about 100 individual dopants with ultra-low spectral diffusion, ∼ 0.1 MHz, determined by the nuclear spin bath [6]. Using nuclear spin initialization or silicon instead of silicate host crystals may further reduce this value below the 20 kHz homogeneous linewidth we observed recently in a nanophotonic waveguide [2]. This would enable the realization of entanglement between remote dopants with high efficiency and fidelity. Thus, our novel hardware platform may facilitate the implementation of scalable quantum networks and repeaters based on single emitters at telecom wavelength.
References
[1] L. Weiss, A. Gritsch, B. Merkel, A. Reiserer, Optica 8, 40 (2021).
[2] A. Gritsch, L. Weiss, J. Früh, S. Rinner, A. Reiserer, ArXiv:2108.05120 (2021).
[3] B. Merkel, A. Ulanowski, A. Reiserer, Phys. Rev. X 10, 041025 (2020).
[4] P. Cova Fari˜na, B. Merkel, N. Herrera Valencia, P. Yu, A. Ulanowski, A. Reiserer, Phys. Rev. Applied 15, 064028 (2021).
[5] B. Merkel, P. Cova Farina, A. Reiserer, Phys. Rev. Lett. 127, 030501 (2021).
[6] A. Ulanowski, B. Merkel, A. Reiserer, ArXiv:2110.09409 (2021).
[7] M. Rancic, M. P. Hedges, R. L. Ahlefeldt, M. J. Sellars, Nat. Phys. 14, 50 (2018).
[8] S. Chen, M. Raha, C. M. Phenicie, S. Ourari, J. D. Thompson, Science 370, 592 (2020)
▶ About the MCQST Conference 2022:
The Munich Conference on Quantum Science and Technology 2022 brings together the Munich quantum community with international invited guests in academia and industry for three days of talks and poster sessions. Join hundreds of guests from around the world in the beautiful Bavarian Alps from July 4-6, 2022 to exchange ideas, learn about innovative research, and discuss the latest advancements in all fields of quantum science and technology.
MCQST
▶ Conference: https://www.mcqst.de/conference2022/o...
▶ Website: https://www.mcqst.de
▶ Twitter: / mcqst_cluster
▶ LinkedIn: / mcqst