If we can control the z-distance between the

nanoemitter and the Au nanoarray, it is possible to manipulate the LDOS enhancement as well as the light emission rate. Moreover, the large field and LDOS enhancement can also be demonstrated by the PL measurement [33, 45], and these detailed experimental results can be found in Additional file 1: Figure S4. Since the emission rate see more of nanoemitters is proportional to the LDOS, the increase of LDOS greatly confirms the utilization of the Au nanoarray for light emission-manipulating nanoantennas. The light emission rate manipulation experiment was set up using a time-correlated single-photon counting system [45], and the normalized time-resolved PL spectra are shown in Figure 4. The nanoemitters were commercial quantum dots with emission peak located at 655 nm, and the wavelength of incident laser was tuned to 400 nm with the excitation power of 2 mW. Figure 4a shows the LDOS enhancement in the presence of a dipole with an emission wavelength of 655 nm at 10 nm above the Au nanoarray. An average enhancement of 64 times can be found

Tipifarnib solubility dmso from the calculation results. Compared with the average LDOS enhancement of 75 times at the emission wavelength of 792 nm, it can be seen that the LDOS enhancement region of the Au nanoarray is quite large, which can make the Au nanoarray find useful applications in the design of functional plasmonic devices. In Figure 4b, the PL decay trace of the QDs on SiO2 substrate and pure AAO are single exponential

with the Metabolism inhibitor corresponding emission rate τ = 0.0429 ns−1 on SiO2 and τ = 0.0559 ns−1 on pure AAO. The single-exponential decay trace indicates that the cooperative effects caused by the assembling of QDs can be neglected [18]. On the contrary, the time-resolved PL curve of QDs on Au nanoarray decays in a two-component exponential form: where A f and A s are the weight factors of the fast and slow decay processes, Interleukin-3 receptor respectively, and t f and t s are the corresponding lifetimes (emission rate τ = 1/t). The two-component exponential decay form suggests the strong interaction between QDs and Au nanoarrays. Figure 4 LDOS enhancement and the normalized time-resolved PL spectra of QDs on Au nanoarray. (a) The x-position dependence of LDOS enhancement at the wavelength of 655 nm. An average LDOS enhancement of 64 times can be achieved. (b) The normalized time-resolved PL spectra of QDs with emission peak located at 655 nm. The emission rate of QDs increases from 0.0429 to 0.5 ns−1 by the existence of the Au nanoarray, showing an enhancement of 10.7 times. From the data in Figure 4, t s is 23.3 ns, while t f is 2.0 and 3.4 ns for QDs on uniform and nonuniform Au nanoarrays, respectively.