Department of Physics , University of California , Berkeley , California 97403 , United States.
Materials Sciences Division , Lawrence Berkeley National Laboratory , Berkeley , California 94720 , United States.
Nano Lett. 2018 Apr 11;18(4):2683-2688. doi: 10.1021/acs.nanolett.8b00632. Epub 2018 Apr 2.
Quantum emitters in two-dimensional hexagonal boron nitride (hBN) are attractive for a variety of quantum and photonic technologies because they combine ultra-bright, room-temperature single-photon emission with an atomically thin crystal. However, the emitter's prominence is hindered by large, strain-induced wavelength shifts. We report the discovery of a visible-wavelength, single-photon emitter (SPE) in a zero-dimensional boron nitride allotrope (the boron nitride nanococoon, BNNC) that retains the excellent optical characteristics of few-layer hBN while possessing an emission line variation that is lower by a factor of 5 than the hBN emitter. We determined the emission source to be the nanometer-size BNNC through the cross-correlation of optical confocal microscopy with high-resolution scanning and transmission electron microscopy. Altogether, this discovery enlivens color centers in BN materials and, because of the BN nanococoon's size, opens new and exciting opportunities in nanophotonics, quantum information, biological imaging, and nanoscale sensing.
二维六方氮化硼（hBN）中的量子发射器因其结合了超亮、室温单光子发射和原子级薄晶体而在各种量子和光子技术中具有吸引力。然而，由于大的应变诱导波长偏移，发射器的突出性受到阻碍。我们报告了在零维氮化硼同素异形体（氮化硼纳米茧，BNNC）中发现了可见波长的单光子发射器（SPE），它保留了少层 hBN 的优异光学特性，同时具有比 hBN 发射器低 5 倍的发射线变化。我们通过光学共焦显微镜与高分辨率扫描和透射电子显微镜的交叉相关确定了发射源是纳米尺寸的 BNNC。总的来说，这一发现激发了 BN 材料中的色心，并且由于 BN 纳米茧的尺寸，为纳米光子学、量子信息、生物成像和纳米尺度传感开辟了新的令人兴奋的机会。
