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Luminescent Diamond: A Platform for Next Generation Nanoscale Optically Driven Quantum Sensors
Published in Odireleng Martin Ntwaeaborwa, Luminescent Nanomaterials, 2022
Nicholas Nunn, Alexander I. Shames, Marco Torelli, Alex I. Smirnov, Olga Shenderova
We categorize three general schemes for which optical centers in diamond can be deployed as sensors, summarized in Fig. 1.12. We remark that this categorization is somewhat arbitrary and a matter of opinion; however, it is inclusive of many of the commonly encountered and employed sensing methodologies in the literature. The three general categories are: Time resolved luminescence intensity measurements;Optically detected magnetic resonance, including both CW and pulsed methods;Direct all-optical readout of spectral feature shifts and fluorescence intensity.
Diamond Nanothermometry
Published in Klaus D. Sattler, 21st Century Nanoscience – A Handbook, 2020
Yuen Yung Hui, Oliver Y. Chen, Huan-Cheng Chang, Meng-Chih Su
An important consequence of the optically induced spin polarization as discussed in Section 26.3.1 is that the fluorescence intensity of the NV– centers will reach its maximum after several cycles of the electronic excitation from 3A2 to 3E (Figure 26.1d). Under this condition, when a microwave radiation around 2.87 GHz is applied to the center, the electron spins will undergo a transition from ms = 0 to ms = ±1 sublevels of the ground state. Such a transition will reduce the fluorescence intensity by up to 30%, thus allowing the spin states of the individual NV– centers to be read out optically, a technique known as optically detected magnetic resonance (ODMR).
Electron Paramagnetic Resonance
Published in Grinberg Nelu, Rodriguez Sonia, Ewing’s Analytical Instrumentation Handbook, Fourth Edition, 2019
Sandra S. Eaton, Gareth R. Eaton
Introductions to ENDOR, TRIPLE, and ELDOR are provided in Atherton (1973), Kevan and Kispert (1976), Box (1977), Dorio and Freed (1979), Schweiger (1982), Eachus and Olm (1985), and Chasteen and Snetsinger (2000). A convenient table comparing the techniques is in Poole (1983, p. 650). The conditions needed to observe ENDOR of various nuclei in organic radicals in solution is discussed in detail in Plato et al. (1981). An extensive review of ENDOR covering the period 1978–1989 is in Goslar et al. (1994) and Piekara-Sady and Kispert (1994). Illustrations of TRIPLE provide leading references to the literature (Kurreck et al., 1984; Kirste et al., 1985). A wide range of variations on the basic theme of multiple resonance has been developed, with CW and pulsed methods, field sweep and frequency sweep, and various combinations. Poole (1983) also describes double-resonance experiments in which in addition to the microwave field, there is optical irradiation (optically detected magnetic resonance, ODMR), pulse radiolysis (dynamic electron polarization, DEP), an electric field (Mims, 1976), and acoustic or ultrasonic paramagnetic resonance (UPR) (Devine and Robinson, 1982).
Recent applications of fluorescent nanodiamonds containing nitrogen-vacancy centers in biosensing
Published in Functional Diamond, 2022
Yuchen Feng, Qi Zhao, Yuxi Shi, Guanyue Gao, Jinfang Zhi
In terms of optical properties, the NV- centers emit bright red light (3E→3A) under excitation of green light with a wavelength of 532 nm, and exhibit the zero-phonon line (ZPL) at 637 nm which shows in Figure 1(C). The excited electrons return to the ground state via two possible pathways: (I) by the emission of 637 nm in the ZPL and phonon sideband; (II) firstly into the metastable singlet states (1A) via intersystem crossing (ISC) and an infrared emission of a 1042 nm (1E→1A), further into the ground state with ms = 0 through ISC. The latter pathway results in a decrease in the emitted fluorescence intensity. It should be noted that the ISC rate from the ms = ±1 sublevel of the excited state to the singlet state is higher than that from the ms = 0 sublevel. Thus, the optical pumping can lead to a strong spin polarization into ms = 0 ground state after a few excitation-emission cycles. Besides, pumping with a resonant microwave frequency at 2.87 GHz promotes the electrons to the ms = ±1 states from ms = 0, which reduces the fluorescence intensity by about 30% after several cycles of excitation. That is to say, the spin states of NV− centers can be manipulated by microwave radiations and readout optically. Herein, optically detected magnetic resonance (ODMR) is generally used to detect the spin states and transitions between spin sublevels of NV− centers [29], as shown in Figure 2. The ODMR of NV− in diamond is unique and powerful, which has applications in magnetometry and sensing, biomedical imaging, and quantum information.