Trion quantum coherence in site-controlled pyramidal InGaAs quantum dots

Rares  Barcan; Ioannis Samaras; Kristopher Barr; Konstantinos G. Lagoudakis

doi:10.1038/s41598-025-33282-2

Trion quantum coherence in site-controlled pyramidal InGaAs quantum dots

Rares Barcan
, Ioannis Samaras
, Kristopher Barr
, Konstantinos G. Lagoudakis^*

^*Corresponding author for this work

Physics

Research output: Contribution to journal › Article › peer-review

1 Citation (Scopus)

3 Downloads (Pure)

Abstract

Deterministically positioned pyramidal InGaAs quantum dots (QDs) exhibit exceptional quantum properties, making them highly promising candidates for scalable on-chip quantum information processing. In this work, we investigate the coherent dynamics of positively charged excitons under the influence of strong magnetic fields in the Faraday configuration. Pyramidal quantum dots exhibit a fourfold splitting of the charged excitons even in the Faraday configuration, giving rise to an optically addressable double-Lambda (𝛬) system akin to self-assembled quantum dots in oblique magnetic fields. Here, we investigate ultrafast complete coherent control of the trion to ground state transition utilizing advanced optical resonant excitation techniques and we observe quantum coherence over timescales that are similar to other prominent quantum dot platforms. These results pave the way towards establishing site-controlled pyramidal InGaAs QDs as scalable platforms for quantum information processing, expanding the reach of coherent control to new quantum systems.

Original language	English
Article number	4114
Number of pages	12
Journal	Scientific Reports
Volume	16
Issue number	1
Early online date	22 Jan 2026
DOIs	https://doi.org/10.1038/s41598-025-33282-2
Publication status	Published - 30 Jan 2026

Funding

R.A.B. acknowledges financial support from the EPSRC Doctoral Training Program under grant no. EP/Y011864/1 and the Agency for Student Loans and Scholarships (https://roburse.ro) under the scholarship H.G. no. 118/2023. I.S. acknowledges financial support from the EPSRC Doctoral Training Partnership under grant no. EP/W524670/1. K.B. acknowledges financial support from the EPSRC Doctoral Training Program under grant no. EP/R513349/1. G.J. and E.P. acknowledge funding from Research Ireland, formerly Science Foundation Ireland, under Grants Nos. 22/FFP-P/11530, 22/FFP-A/10930, 15/IA/286.

Keywords

quantum dots
InGaAs
quantum systems

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10.1038/s41598-025-33282-2Licence: CC BY-NC-ND 4.0

Barcan-etal-SR-2026-Trion-quanum-coherence-in-site-controlled-pyramidalFinal published version, 2.57 MBLicence: CC BY-NC-ND 4.0

Cite this

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AU - Barcan, Rares

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Y1 - 2026/1/30

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Trion quantum coherence in site-controlled pyramidal InGaAs quantum dots

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