No Arabic abstract
In the field of quantum photon sources, single photon emitter from solid is of fundamental importance for quantum computing, quantum communication, and quantum metrology. However, it has been an ultimate but seemingly distant goal to find the single photon sources that stable at room or high temperature, with high-brightness and broad ranges emission wavelength that successively cover ultraviolet to infrared in one host material. Here, we report an ultraviolet to near-infrared broad-spectrum single photon emitters (SPEs) based on a wide band-gap semiconductor material hexagonal boron nitride (hBN). The bright, high purity and stable SPEs with broad-spectrum are observed by using the resonant excitation technique. The single photon sources here can be operated at liquid helium, room temperature and even up to 1100 K. Depending on the excitation laser wavelengths, the SPEs can be dramatically observed from 357 nm to 896 nm. The single photon purity is higher than to 90 percentage and the narrowest linewidth of SPE is down to $sim$75 $mu$eV at low temperature, which reaches the resolution limit of our spectrometer. Our work not only paves a way to engineer a monolithic semiconductor tunable SPS, but also provides fundamental experimental evidence to understand the electronic and crystallographic structure of SPE defect states in hBN.
Emitters of indistinguishable single photons are crucial for the growing field of quantum technologies. To realize scalability and increase the complexity of quantum optics technologies, multiple independent yet identical single photon emitters are also required. However typical solid-state single photon sources are inherently dissimilar, necessitating the use of electrical feedback or optical cavities to improve spectral overlap between distinct emitters. Here, we demonstrate bright silicon-vacancy (SiV-) centres in low-strain bulk diamond which intrinsically show spectral overlap of up to 91% and near transform-limited excitation linewidths. Our results have impact upon the application of single photon sources for quantum optics and cryptography, and the production of next generation fluorophores for bio-imaging.
We create and isolate single-photon emitters with a high brightness approaching $10^5$ counts per second in commercial silicon-on-insulator (SOI) wafers. The emission occurs in the infrared spectral range with a spectrally narrow zero phonon line in the telecom O-band and shows a high photostability even after days of continuous operation. The origin of the emitters is attributed to one of the carbon-related color centers in silicon, the so-called G center, allowing purification with the $^{12}$C and $^{28}$Si isotopes. Furthermore, we envision a concept of a highly-coherent scalable quantum photonic platform, where single-photon sources, waveguides and detectors are integrated on a SOI chip. Our results provide a route towards the implementation of quantum processors, repeaters and sensors compatible with the present-day silicon technology.
Quantum technologies require robust and photostable single photon emitters (SPEs) that can be reliably engineered. Hexagonal boron nitride (hBN) has recently emerged as a promising candidate host to bright and optically stable SPEs operating at room temperature. However, the emission wavelength of the fluorescent defects in hBN has, to date, been shown to be uncontrolled. The emitters usually display a large spread of zero phonon line (ZPL) energies spanning over a broad spectral range (hundreds of nanometers), which hinders the potential development of hBN-based devices and applications. We demonstrate bottom-up, chemical vapor deposition growth of large-area, few layer hBN that hosts large quantities of SPEs: 100 per 10x10 {mu}m2. Remarkably, more than 85 percent of the emitters have a ZPL at (580{pm}10)nm, a distribution which is over an order of magnitude narrower than previously reported. Exploiting the high density and uniformity of the emitters, we demonstrate electrical modulation and tuning of the ZPL emission wavelength by up to 15 nm. Our results constitute a definite advancement towards the practical deployment of hBN single photon emitters in scalable quantum photonic and hybrid optoelectronic devices based on 2D materials.
We report the detection of individual emitters in silicon belonging to seven different families of optically-active point defects. These fluorescent centers are created by carbon implantation of a commercial silicon-on-insulator wafer usually employed for integrated photonics. Single photon emission is demonstrated over the [1.1,1.55]-$mu$m range, spanning the O- and C-telecom bands. We analyse their photoluminescence spectrum, dipolar emission and optical relaxation dynamics at 10K. For a specific family, we show a constant emission intensity at saturation from 10K to temperatures well above the 77K-liquid nitrogen temperature. Given the advanced control over nanofabrication and integration in silicon, these novel artificial atoms are promising candidates for Si-based quantum technologies.
Color centers in hexagonal boron nitride have shown enormous promise as single-photon sources, but a clear understanding of electron-phonon interaction dynamics is critical to their development for quantum communications or quantum simulations. We demonstrate photon antibunching in the filtered auto- and cross-correlations $g^{(2)}_{lm}(tau)$ between zero-, one- and two-phonon replicas of defect luminescence. Moreover, we combine autocorrelation measurements with a violation of the Cauchy-Schwarz inequality in the filtered cross-correlation measurements to distinguish a low quantum-efficiency defect from phonon replicas of a bright defect. With no background correction, we observe single photon purity of $g^{(2)}(0)=0.20$ in a phonon replica and cross-spectral correlations of $g^{(2)}_{lm}(0)=0.18$ between a phonon replica and the zero phonon line. These results illustrate a coherent interface between visible photons and mid-infrared phonons and provide a clear path toward control of photon-phonon entanglement in 2D materials.