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The Stokes and the anti-Stokes Raman spectra from the high energy carbon-carbon stretching modes in graphene and diamond are studied, with a focus on their intensity dependence on the excitation laser power. For diamond, the experiment was performed on a 50 μm slice of chemical vapour deposition grown single crystal using a 785 nm laser, in both the continuous wave (CW) and pulsed mode-locked (ML-130 fs pulses) excitation regimes. For graphene, the experiments were performed on suspended samples, including single layer, bilayer with AB-staking, twisted bi-layer and a sample with 4-6 layers, using λ = 532 and 633 nm CW lasers. The Stokes and anti-Stokes intensities vary largely from sample to sample, and the anti-Stokes/Stokes intensity ratio shows different excitation laser power behaviours. These differences can be explained on the basis of laser heating or correlated Stokes-anti-Stokes scattering phenomena. [ABSTRACT FROM AUTHOR]

The burgeoning field of nanophotonics has grown to be a major research area, primarily because of the ability to control and manipulate single quantum systems (emitters) and single photons on demand. For many years, studying nanophotonic phenomena was limited to traditional semiconductors (including silicon and GaAs) and experiments were carried out predominantly at cryogenic temperatures. In the last decade, however, diamond has emerged as a new contender to study photonic phenomena at the nanoscale. Offering a plethora of quantum emitters that are optically active at room temperature and ambient conditions, diamond has been exploited to demonstrate super‐resolution microscopy and realize entanglement, Purcell enhancement, and other quantum and classical nanophotonic effects. Elucidating the importance of diamond as a material, this progress report highlights the recent achievements in the field of diamond nanophotonics, and conveys a roadmap for future experiments and technological advancements. [ABSTRACT FROM AUTHOR]

Energy transfer between fluorescent probes lies at the heart of many applications ranging from bio‐sensing and bio‐imaging to enhanced photodetection and light harvesting. In this work, Förster resonance energy transfer (FRET) between shallow defects in diamond—nitrogen‐vacancy (NV) centers—and atomically thin, 2D materials—tungsten diselenide (WSe2)—is studied. By means of fluorescence lifetime imaging, the occurrence of FRET in the WSe2/NV system is demonstrated. Further, it is shown that in the coupled system, NV centers provide an additional excitation pathway for WSe2 photoluminescence. The results constitute the first step toward the realization of hybrid quantum systems involving single‐crystal diamond and 2D materials that may lead to new strategies for studying and controlling spin transfer phenomena and spin valley physics. [ABSTRACT FROM AUTHOR]