Figure 1 | Scientific Reports

Figure 1

From: Observation of the linewidth broadening of single spins in diamond nanoparticles in aqueous fluid and its relation to the rotational Brownian motion

Figure 1

(a) Schematic drawing of a single nanodiamond gradually detached from a coverslip it was attached to. The nanodiamond orientation (NV axis) is fluctuating to detach. (b) Close up of the central part of the experimental setup. The nanodiamond is placed in a home-made perfusion chamber that simultaneously allows exchange of the solution and the optical experiment. A thin copper wire is fed through into the chamber for the spin excitation. Single NV centers hosted in nanodiamonds are excited by 532-nm laser light and are observed with red-shifted fluorescence collected through the same microscope objective. (c) Energy diagram of NV centers. The main optical transition occurs between the ground state (|A3〉) and the excited state (|E3〉). Microwave excites the electron spin from |0〉 to |±1〉 in the sub-states of |A3〉, followed by spin-conserving optical transitions and intersystem crossing from |±1〉 states in |E3〉 to the lower singlet state, (|A1〉). The population in |A1〉 is nonradiatively relaxed to the spin |0〉 state of the triplet ground state, which causes a decrease of the fluorescence intensity.