Ultra-small Mode Volume Polariton Condensation via Precision $He^+$ Ion Implantation

Y. C. Balas; X. Zhou; E. Cherotchenko; I. Kuznetsov; S. K. Rajendran; G. G. Paschos; A. V. Trifonov; A. Nalitov; H. Ohadi; P. G. Savvidis

arXiv · 2506.22202

Ultra-small Mode Volume Polariton Condensation via Precision $He^+$ Ion Implantation

Y. C. Balas·X. Zhou·E. Cherotchenko·I. Kuznetsov·S. K. Rajendran·G. G. Paschos·A. V. Trifonov·A. Nalitov·H. Ohadi·P. G. Savvidis

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Abstract

We present a novel method for generating potential landscapes in GaAs microcavities through focused $He^{+}$ implantation. The ion beam imprints micron-scale patterns of non-radiative centers that deplete the exciton reservoir and form a loss-defined potential minimum. Under non-resonant pumping, the resulting traps have a lateral size $\le 1.2 ~\mathrm{\mu m}$ and a three-dimensional mode volume of only $\approx 0.6 ~ \mathrm{\mu m^3}$, small enough to to support a single polariton condensate mode. The implantation process maintains strong coupling and provides lithographic ($ < 300 ~ \mathrm{nm}$) resolution. These loss-engineered traps effectively overcome the micrometer-scale limitations of conventional microcavity patterning techniques, opening new avenues for device development and polariton research within the quantum regime.

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Y. C. Balas, X. Zhou, E. Cherotchenko, I. Kuznetsov, S. K. Rajendran, G. G. Paschos, A. V. Trifonov, A. Nalitov, H. Ohadi, P. G. Savvidis. 2025-06-27. Ultra-small Mode Volume Polariton Condensation via Precision $He^+$ Ion Implantation. https://arxiv.org/abs/2506.22202

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