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Significant advances have been made in fundamental research of topological insulators (TIs), yet their device applications remain elusive. We propose an approach towards seamless integration of two-dimensional (2D) TIs into semiconductor devices. Using first-principles calculations, we show that heteroepitaxially grown III-V semiconductor ultrathin films can self-convert into 2D TIs. Remarkably, on GaSb(111) monolayer GaAs1-xBix becomes universally a 2D TI at any alloy concentration, x, enabled by natural formation of semiconductor heterojunctions. For the GaAs-rich monolayer, having type-II (III) band alignment with GaSb, an intriguing interfacial band offset inversion emerges between surface Ga-s and substrate Sb-p bands; for the GaBi-rich monolayer, with type-I (I’) alignment, the conventional intra-surface band gap inversion arises between Ga-s and Bi-p bands. The lattice-matching epitaxy of GaAs0.25Bi0.75 alloy enables growth of thin-film 2D TIs with a gap up to ~330 meV. Our findings pave the way to engineering wafer-scale large-gap 2D TIs to potentially operate at room temperature.

Quantum sensors based on frequentist interferometry face a trade off between sensitivity and dynamic range Bayesian quantum estimation, combining Bayesian statistics with quantum metrology, can surpass the limit of conventional frequentist measurements For cold atom CPT clocks, our adaptive Bayesian protocol achieves Heisenberg limited sensitivity in integration time and improves fractional frequency stability by 5 1 4 dB over conventional PID locking while enhancing robustness against technical noise In CPT magnetometry, we optimize measurement sequences to improve precision scaling from T 0 5 to T 0 85 Using Bayesian quantum estimation to optimize the interferometry sequence, we yield a 145 6 nT dynamic range 14 6 dB higher than frequentist counterpart of 5 0 nT) with a sensitivity of 6 8 0 1 pT/Hz¹ ² 3 3 dB improvement over the frequentist counterpart of 14 7 0 4 pT/Hz¹ ²) In addition to atomic clocks and magnetometers, this framework may bridge high sensitivity and broad dynamic range for other interferometry based quantum sensors.

The HK Institute of Quantum Science & Technology (HKIQST) 香港大学香港量子研究院at The University of Hong Kong (HKU) and the Institute for Advanced Study (IAS) of Sun Yat-sen University (SYU) 中山大学高等研究院 have officially signed a Memorandum of Understanding (MOU) to deepen collaboration in quantum science and technology across the Greater Bay Area. The MOU, signed on October 11, 2025, by Professor Zidan Wang (汪子丹) on behalf of HKU IQST and Professor Daoxin Yao (姚道新) representing Sun Yat-sen University IAS, marks a significant step toward building a strategic partnership between two leading academic institutions in the region. Under the agreement, both parties will: · Serve as a bridge for collaborative research between HKU and Sun Yat-sen University in advanced quantum technologies and related fields. · Jointly participate in academic activities across the Greater Bay Area, including establishing shared research platforms and applying for strategic funding opportunities. · Promote the exchange of researchers, including professors, visiting scholars, and graduate students, and co-host academic events such as forums, workshops, and summer schools. The MOU also outlines mutual commitments to confidentiality, dispute resolution, and responsible use of institutional branding, ensuring a respectful and productive partnership. This collaboration reflects a shared vision to accelerate innovation, foster academic exchange, and contribute to the development of quantum science in the region. 🔗 Learn more about HKU IQST: https://iq.hku.hk 🔗 Visit Sun Yat-sen University IAS: https://iash.sysu.edu.cn