Advances in Nanoengineering seminar – November 10, 2026
We cordially invite you to Advances in Nanoengineering seminar, which will be held on November 10, 2026 at 13.15 in room 321, building A-1, where
Hanna Salamon
from Niels Bohr Institute, University of Copenhagen
will deliver a lecture titled:
Integrated Photonic Circuits in GaAs for Quantum Technologies
The lecture abstract is attached below.
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The development of practical quantum photonic technologies requires the deterministic generation and manipulation of quantum states of light within scalable, reconfigurable photonic circuits. Semiconductor quantum dots (QDs) in GaAs are a leading platform for on-chip single-photon generation, offering bright, coherent, and highly indistinguishable emission [1]. Their integration into p-i-n diodes further enables charge-noise suppression and electrical tuning of the QD emission [2]. However, integrating these high-performance emitters with reconfigurable photonic circuitry while preserving their optical properties remains challenging. In particular, cryogenic operation and spectral tunability impose constraints on switching and routing of photons. One promising approach is to exploit nano-electromechanical systems (NEMS) [3, 4], which enable compact, low-loss, and energy-efficient reconfigurable components directly in GaAs. Alternatively, heterogeneous integration with mature silicon photonics offers a way to combine the high coherence of III–V quantum emitters with the scalability and functionality of established silicon photonic platforms [5, 6].
In this presentation, I will discuss two complementary approaches for integrating QDs in GaAs with scalable photonic architectures. First, I will present a monolithic GaAs platform combining electrically controlled QDs with a reconfigurable nanomechanical router [7]. This approach enables the simultaneous control of QD-based single photon emitters with reconfigurable elements at cryogenic temperatures. System-level integration enables individual electrical and optical addressing of active components on a single chip, allowing their concurrent operation while preserving coherent non-classical light emission.
Second, I will present a heterogeneous integration approach in which electrically controlled QDs embedded in GaAs waveguides are integrated with silica and low-loss silicon nitride (SiN) photonic circuits through die-to-die adhesive bonding [8]. The resulting GaAs-on-insulator platform incorporates electrically controlled QDs demonstrating narrow optical linewidths below 2 μeV and high single-photon purity, with g²(0)=(5.2±0.8)% comparable to that of unprocessed GaAs devices [9].
Together, these approaches demonstrate complementary pathways towards integrating high-performance quantum emitters with functional and scalable photonic circuitry, providing promising building blocks for reconfigurable quantum photonic technologies.
[1] R. Uppu et al., Science advances 6, eabc8268 (2020).
[2] F. T. Pedersen et al., ACS Photonics 7, 2343 (2020).
[3] L. Midolo, A. Schliesser, and A. Fiore, Nature nanotechnology 13, 11 (2018).
[4] C. Errando-Herranz et al., IEEE Journal of Selected Topics in Quantum Electronics 26, 1 (2019).
[5] A. W. Elshaari et al., Nature Photonics, 14, 285-298 (2020).
[6] M. I. Davanco et al., Nature Communications 8, 889 (2017).
[7] H. Salamon et al., arXiv preprint arXiv:2610.06451 (2026)
[8] H. Salamon et al., Nano Letters 25.46, 16366-16371 (2025).
[9] M. C. Löbl et al., arXiv preprint arXiv:1708.00520 (2017).
