1887
banner image
No data available.
Please log in to see this content.
You have no subscription access to this content.
No metrics data to plot.
The attempt to load metrics for this article has failed.
The attempt to plot a graph for these metrics has failed.
Quantitative evaluation of blinking in surface enhanced resonance Raman scattering and fluorescence by electromagnetic mechanism
Rent:
Rent this article for
USD
10.1063/1.3675567
/content/aip/journal/jcp/136/2/10.1063/1.3675567
http://aip.metastore.ingenta.com/content/aip/journal/jcp/136/2/10.1063/1.3675567
View: Figures

Figures

Image of FIG. 1.
FIG. 1.

Fundamental observation from Ag NP dimer/R6G: (a1)–(a3) spectra of plasmon resonance, (b1)–(b3) those of SERRS and SEF, and (c1)–(c3) SEM images obtained from three Ag dimers. Model for a Ag dimer generating SERRS: (d1) electric field distribution around a Ag dimer calculated by FDTD, (d2) enlarged image of a crevasse in the Ag dimer, and (d3) assumed location of a molecule at the crevasse.

Image of FIG. 2.
FIG. 2.

Total intensity of SERRS and SEF from three representative Ag dimer: (a1) temporally stable, (a2) fluctuating, and (a3) intermittent. Intensity is integrated from 540 to 700 nm. SERRS and SEF from three representative Ag dimer: (b1)–(b3) temporally stable, (c1)–(c3) fluctuating, and (d1)–(d3) intermittent. Time lapse for the measurement is indicated in each figure. Exposure time for each spectrum is 5 s.

Image of FIG. 3.
FIG. 3.

Temporal changes in (a1)–(a4) plasmon resonance spectra, (b1)–(b4) SERRS and SEF spectra, and (c1)–(c4) total SERRS and SEF intensity integrated from 540 to 700 nm, all of which were measured from single Ag dimer after irradiating 1064-nm laser pulses. The number of the irradiated laser pulses is indicated in each figure. Note that two panels in (b4) shows spectral fluctuation observed just after irradiating six pulses without further laser pulse irradiation.

Image of FIG. 4.
FIG. 4.

Key experimental parameters for quantitative evaluation of SERRS and SEF blinking: (a) Evaluating I SERRS/I SEF for panels (d). Total SERRS intensity I SERRS and SEF intensity I SEF were averaged over I SERRS1 to I SERRS6 (red arrows) and that of I SEF1 to I SEF6 (green arrows), respectively. (b) σ RRS of spectrum R6G in an aqueous solution. Raman intensity is defined as an upper part of the red curve that is considered as back ground fluorescence. The unit of y-axis is converted into cross section (cm2/nm) based on Refs. 31 and 32. (c) σ FL spectrum of R6G in an aqueous solution detected with the same experimental setup. The unit of y-axis is converted into cross section (cm2/nm) based on Refs. 31 and 32. (d) Normalized standard deviation scores S dependence of |M d|2 in 0 < S < 0.6 for eight dimers denoted by eight symbols (○, ○, □, ▵,∇, ◊, +, and ×). Blue outline circles are taken from the Ag dimer used for 3. Number of irradiated laser pulses is indicated by colors. Gray color indicates before laser pulse irradiation, and faint blue, green, orange, and red indicate after first, second, third, and fourth laser pulse irradiation. (e) |M EM| (= (I SERRS/σ RRS)1/2) dependence of |M d|2 (= I SERRS/I SEF × σ RRS/σ FL) for the same eight dimers as those in (d).

Image of FIG. 5.
FIG. 5.

Evaluation of SEF fluctuation: (a) S dependence of |M d|2 in 0 < S < 2.0 for the same eight dimers as those in Fig. 4(a). Fluctuation in |M d|2 is highlighted by binary points (red arrows). Blue outline circles are taken from the Ag dimer used for Fig. 3(b)σ FL spectrum of R6G in an aqueous solution detected with the same experimental setup. (c1), (c2), and (d1)–(d3) Intensity fluctuation in SERRS and SEF spectra from two Ag dimers just after irradiating six and four pulses without irradiating further pulse, respectively. Detection periods are indicated in each figure. The fluorescence intensity that dominantly fluctuated is highlighted by green arrows.

Image of FIG. 6.
FIG. 6.

Evaluation of EM enhancement factor: (a) σ o total of an ensemble Ag NPs/R6G aggregates (black line). Here, I SERRS/I SEF = 0.58 (|M d|2 = 7.25 × 104) from σ o total. Blue trace represents FL/|M d|2, where k = 1 – 0.58/0.84. (b) σ total of a Ag dimer/R6G. Here, I SERRS/I SEF = 0.84. (c) Graphical presentation of deriving |M EM|2 from Eq. (7). Note that I SERRS/I SEF in σ o total FL/|M d|2 is adjusted to 0.84, which is the same as I SERRS/I SEF in σ total, using k = 1 – 0.58/0.84.

Image of FIG. 7.
FIG. 7.

Relationship between EM enhancement factor and plasmon resonance maxima: (a1)–(a6) spectral changes in plasmon resonance (black lines) and |M EM|2 (red lines) from a Ag dimer measured after irradiating 1064-nm laser pulses. The number of the NIR pulses and I SERRS/I SEF are indicated in each figure. I SERRS/I SEF is obtained in the same manner as that for Fig. 4(a). Spectra of σ total in Figs. 3(b1)–3(b4) are used for obtaining I SERRS/I SEF. The Ag dimer is the same as that used for Fig. 3(b). Maximum wavelength λ p of plasmon resonance dependence of maximum wavelength λ M of |M EM|2 for eight dimers denoted by eight symbols (○, ○, □, ▵,∇, ◊, +, and ×). (c) λ p dependence of maximum value |M EMmax | 2 of |M EM|2 for the eight dimers. Inset is calculated |M EMmax | 2 against λ p assuming a Lorentzian line shape for plasmon resonance. Red lines are fitted curves. Number of irradiated laser pulses is indicated by colors. Gray color indicates before NIR laser pulse irradiation, and faint blue, green, orange, red, brown, and moss green indicate after first, second, third, fourth, fifth, and sixth NIR laser pulse irradiation. (d) S dependence of |M EMmax | 2 for the eight dimers. Open circles (blue) in (b)–(d) are taken from (a1)–(a6).

Loading

Article metrics loading...

/content/aip/journal/jcp/136/2/10.1063/1.3675567
2012-01-11
2014-04-25
Loading

Full text loading...

This is a required field
Please enter a valid email address
752b84549af89a08dbdd7fdb8b9568b5 journal.articlezxybnytfddd
Scitation: Quantitative evaluation of blinking in surface enhanced resonance Raman scattering and fluorescence by electromagnetic mechanism
http://aip.metastore.ingenta.com/content/aip/journal/jcp/136/2/10.1063/1.3675567
10.1063/1.3675567
SEARCH_EXPAND_ITEM