DOI: 10.1021/jp022399e. Local Electric Field and Scattering Cross Section of Ag Nanoparticles under Surface Plasmon Resonance by Finite Difference Time Domain Method

Local Electric Field and Scattering Cross Section of Ag Nanoparticles under Surface Plasmon Resonance by Finite Difference Time Domain Method

10.1021/jp022399e

Crossref journal-article

American Chemical Society (ACS)

The Journal of Physical Chemistry B (316)

Bibliography

Futamata, M., Maruyama, Y., & Ishikawa, M. (2003). Local Electric Field and Scattering Cross Section of Ag Nanoparticles under Surface Plasmon Resonance by Finite Difference Time Domain Method. The Journal of Physical Chemistry B, 107(31), 7607â7617.

Authors 3

M. Futamata (first)
Y. Maruyama (additional)
M. Ishikawa (additional)

References 36 Referenced 282

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The factor of 1014is referred as the value for SMS based on the comparison with fluorescence spectroscopy. In our facility, however, the enhancement necessary for SMS is 1010as explained here. Detected photons for Raman scattering from a single molecule is given byNobs= (NL/S)ρSS× ∫ (d2σ/dΩ dω) dω ΔΩηsys. HereNobs= detected signal counts, (NL/S) = incident photon numbers per unit area, ρS= molecular density (molecules/area),S= irradiated area, (d2σ/dΩ dω) = differential scattering cross section, and ηsys= spectrometer efficiency × detector sensitivity/efficiency (counts/photon). When the incident Ar+laser power is 100 μW/μm2at 488 nm, the photon flux of 2.5 × 1014photons/s irradiates the sample. If the scattering cross section of the sample is enhanced to 10-16cm2, similar to the fluorescence signal, a Raman signal of 37 500 counts/s is obtained from the parameters (NL/S) = 100 μW/μm2= 2.5 × 1022photons/(s·cm2), ρSS= 1, (d2σ/dΩ dω) = 10-16cm2, and ηsys=QpolyQeA= 0.3 × 0.5 × 0.1 = ca. 0.015. The signal intensity is much stronger than the detection limit as the noise level of our facility is ca. 1 count/s. Thus, the enhancement of 1.3 × 1010is sufficient to detect the Raman signal from an isolated molecule with a signal-to-noise ratio of 5 according to 1014/(37 500/5)=1.3 × 1010. As reported in this paper, this value can be achieved only with electromagnetic mechanism.
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Dates

Type	When
Created	22 years ago (July 31, 2003, 1:39 a.m.)
Deposited	2 years, 5 months ago (March 15, 2023, 8:11 a.m.)
Indexed	5 days, 15 hours ago (Aug. 21, 2025, 12:41 p.m.)
Issued	22 years, 1 month ago (July 4, 2003)
Published	22 years, 1 month ago (July 4, 2003)
Published Online	22 years, 1 month ago (July 4, 2003)
Published Print	22 years ago (Aug. 1, 2003)

Funders 0

None

BibTeX

@article{Futamata_2003, title={Local Electric Field and Scattering Cross Section of Ag Nanoparticles under Surface Plasmon Resonance by Finite Difference Time Domain Method}, volume={107}, ISSN={1520-5207}, url={http://dx.doi.org/10.1021/jp022399e}, DOI={10.1021/jp022399e}, number={31}, journal={The Journal of Physical Chemistry B}, publisher={American Chemical Society (ACS)}, author={Futamata, M. and Maruyama, Y. and Ishikawa, M.}, year={2003}, month=jul, pages={7607–7617} }

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      "unstructured": "The factor of 1014is referred as the value for SMS based on the comparison with fluorescence spectroscopy. In our facility, however, the enhancement necessary for SMS is 1010as explained here. Detected photons for Raman scattering from a single molecule is given byNobs= (NL/S)\u03c1SS\u00d7 \u222b (d2\u03c3/d\u03a9 d\u03c9) d\u03c9 \u0394\u03a9\u03b7sys. HereNobs= detected signal counts, (NL/S) = incident photon numbers per unit area, \u03c1S= molecular density (molecules/area),S= irradiated area, (d2\u03c3/d\u03a9 d\u03c9) = differential scattering cross section, and \u03b7sys= spectrometer efficiency \u00d7 detector sensitivity/efficiency (counts/photon). When the incident Ar+laser power is 100 \u03bcW/\u03bcm2at 488 nm, the photon flux of 2.5 \u00d7 1014photons/s irradiates the sample. If the scattering cross section of the sample is enhanced to 10-16cm2, similar to the fluorescence signal, a Raman signal of 37\u2009500 counts/s is obtained from the parameters (NL/S) = 100 \u03bcW/\u03bcm2= 2.5 \u00d7 1022photons/(s\u00b7cm2), \u03c1SS= 1, (d2\u03c3/d\u03a9 d\u03c9) = 10-16cm2, and \u03b7sys=QpolyQeA= 0.3 \u00d7 0.5 \u00d7 0.1 = ca. 0.015. The signal intensity is much stronger than the detection limit as the noise level of our facility is ca. 1 count/s. Thus, the enhancement of 1.3 \u00d7 1010is sufficient to detect the Raman signal from an isolated molecule with a signal-to-noise ratio of 5 according to 1014/(37\u2009500/5)=1.3 \u00d7 1010. As reported in this paper, this value can be achieved only with electromagnetic mechanism."
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        4
      ]
    ]
  },
  "references-count": 36,
  "journal-issue": {
    "issue": "31",
    "published-print": {
      "date-parts": [
        [
          2003,
          8,
          1
        ]
      ]
    }
  },
  "alternative-id": [
    "10.1021/jp022399e"
  ],
  "URL": "http://dx.doi.org/10.1021/jp022399e",
  "relation": {},
  "ISSN": [
    "1520-6106",
    "1520-5207"
  ],
  "subject": [],
  "container-title-short": "J. Phys. Chem. B",
  "published": {
    "date-parts": [
      [
        2003,
        7,
        4
      ]
    ]
  }
}