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A hybrid quantum thermometer composed of bulk diamond with ensemble NV centers and gadolinium magnetic flux concentrators, achieves a submicrokelvin resolution. Near the critical point, the spin resonance to temperature is about 774 times enhanced compared with that of bare NV centers.

This work bridges topology and quantum metrology, demonstrating how topological characteristics within band structures, namely Berry curvature and Chern number, set fundamental limits on metrological properties, with experimental validation in an emulated Chern insulator.

By engineering electric potential of a trapped electron system, the motional states of the trapped electron can obtain giant electric dipole moments, exceeding those attainable with Rydberg atoms. This artificial electric dipole may provide a potential platform for quantum technologies such as ultrahigh-sensitivity electric-field sensing.

Entanglement is NOT free! A strong precision limit of quantum metrology accounting for the preparation complexity of many-particle entangled states is established, revealing a fundamental constraint for reaching the elusive Heisenberg limit and identifying the essential features of many-body systems for achieving the quantum advantage.

Quantum sensing exploits fascinating features of quantum phenomena. A framework utilizing critical quantum dynamics to enhance the sensing performance is developed, providing an experimentally feasible pathway towards the implementation of criticality-enhanced quantum sensing.

Efforts are put into extending quantum enhanced sensing into the non-Hermitian regime of quantum world! A pseudo-Hermitian single-qubit sensor without involving the exceptional point is designed, demonstrating potential advantages to overcome noises that cannot be averaged out by repetitive measurements

Quantum tomography constitutes the family of quantum technologies. A new principle for efficiently inferring the full state of a quantum system by randomly shaking a single local qubit of a network is established, providing the quantum science and engineering communities a much-needed solution for measuring complex systems with limited access.

Geometry and topology of quantum states, characterized by the quantum geometric tensor (QGT), are fundamental concepts in quantum mechanics. A first experimental measurement of the complete QGT by parametric modulations of the quantum system is demonstrated, establishing coherent dynamical responses as a versatile probe for quantum geometry and topology.

A two-level quantum probe under pulsed control allows to reconstruct quantum state of dark systems that are inaccessible for direct control and measurements.

Periodic driving is crucial for both coherent quantum control and fundamental concepts in quantum dynamics. A Raman transition between Floquet synthetic levels in a weakly driven solid-state spin system is successfully observed, offering new possibilities to the communities of efficient quantum control and quantum simulation.