Quantum Emission Properties of Hexagonal Boron Nitride

Hexagonal boron nitride (hBN) is a two-dimensional van der Waals crystal distinguished by a wide band gap and atomically flat structure. Intrinsic and engineered point defects in hBN act as bright, photostable single-photon emitters at room temperature, with narrow optical linewidths and rapid recombination rates. The strong localisation of electronic states around boron-vacancy centres or carbon-related defects gives rise to spin-triplet ground states that can be optically addressed and coherently manipulated. Spectral tunability is achieved via strain, local electric fields or chemical environment, while dynamical decoupling and micro-fabrication enable prolonged spin coherence and integration into photonic architectures. These combined properties position hBN as a versatile platform for on-chip quantum light sources, room-temperature spin qubits and nanoscale quantum sensors with applications ranging from secure communications to biological imaging and materials analysis.

Research from Nature Portfolio

Recent studies have demonstrated quantum coherent control of individual spin defects in hBN under ambient conditions. A carbon-related centre was shown to possess a spin-triplet ground manifold, with coherence times extended through tailored decoupling protocols, paving the way for room-temperature spin-photon interfaces. Investigations into ensembles of negatively charged boron vacancies have revealed that many-body interactions dominate dephasing at high defect densities; by applying advanced dynamical decoupling sequences, researchers achieved a more than fivefold enhancement of coherence times and quantified the charge-state distribution and electric-field susceptibility of these centres. Complementary work has reported the first optically detected magnetic resonance from single defects at room temperature, uncovering distinct photon-bunching dynamics, bipolar resonance contrasts and fine zero-field splitting—key features for robust qubit readout and magnetic sensing.

Quantum Emission Properties of Hexagonal Boron Nitride publication trend

The graph below shows the total number of articles in quantum emission properties of hexagonal boron nitride across all publications each year (not limited to Nature Index journals).

Technical terms

Hexagonal boron nitride (hBN): A two-dimensional wide-bandgap insulator composed of alternating boron and nitrogen atoms in a hexagonal lattice.

Single-photon emitter: A quantum system that emits one photon at a time, essential for secure quantum communications.

Spin coherence: The preservation of a quantum spin state’s phase relationship over time, critical for qubit performance.

Optically detected magnetic resonance (ODMR): A technique that monitors changes in luminescence as a magnetic resonance condition is met, enabling spin state readout.

Dynamical decoupling: A sequence of control pulses applied to a spin qubit to mitigate environmental noise and extend coherence.

Boron vacancy defect (VB–): A missing boron atom in hBN that traps an extra electron, forming an optically active spin centre.

Van der Waals material: A layered crystal held together by weak interlayer forces, allowing facile exfoliation to atomically thin sheets.

References

1. A quantum coherent spin in hexagonal boron nitride at ambient conditions. Nature Materials (2024).
2. Solid‐State Single‐Photon Sources: Recent Advances for Novel Quantum Materials. Advanced Functional Materials (2024).
3. Quantum sensing with optically accessible spin defects in van der Waals layered materials. Light: Science & Applications (2024).
4. Coherent dynamics of strongly interacting electronic spin defects in hexagonal boron nitride. Nature Communications (2023).
5. Tunable and high-purity room temperature single-photon emission from atomic defects in hexagonal boron nitride. Nature Communications (2017).
6. Ab initio theory of the negatively charged boron vacancy qubit in hexagonal boron nitride. npj Computational Materials (2020).
7. Room-temperature optically detected magnetic resonance of single defects in hexagonal boron nitride. Nature Communications (2022).