Limits...
Single Nanoparticle Detection Using Far-field Emission of Photonic Molecule around the Exceptional Point.

Zhang N, Liu S, Wang K, Gu Z, Li M, Yi N, Xiao S, Song Q - Sci Rep (2015)

Bottom Line: In addition to typical mode splitting, we find that the far-field pattern of the PM is significantly changed.Taking a heteronuclear diatomic PM as an example, we demonstrate that a single nanoparticle, whose radius is as small as 1 nm to 7 nm, can be simply monitored through the variation of the far-field pattern.In addition, this research will illuminate new advances in single nanoparticle detection.

View Article: PubMed Central - PubMed

Affiliation: Integrated Nanoscience Lab, Department of Electrical and Information Engineering, Harbin Institute of Technology, Shenzhen, 518055, China.

ABSTRACT
Highly sensitive, label-free detection methods have important applications in fundamental research and healthcare diagnostics. To date, the detection of single nanoparticles has remained largely dependent on extremely precise spectral measurement, which relies on high-cost equipment. Here, we demonstrate a simple but very nontrivial mechanism for the label-free sizing of nanoparticles using the far-field emission of a photonic molecule (PM) around an exceptional point (EP). By attaching a nanoparticle to a PM around an EP, the main resonant behaviors are strongly disturbed. In addition to typical mode splitting, we find that the far-field pattern of the PM is significantly changed. Taking a heteronuclear diatomic PM as an example, we demonstrate that a single nanoparticle, whose radius is as small as 1 nm to 7 nm, can be simply monitored through the variation of the far-field pattern. Compared with conventional methods, our approach is much easier and does not rely on high-cost equipment. In addition, this research will illuminate new advances in single nanoparticle detection.

No MeSH data available.


Related in: MedlinePlus

The far-field patterns of the same resonance as Fig. 2.The radius of nanoparticle is r2 = 0 nm (a), 2 nm (b), 4 nm (c), and 7 nm (d). (e) shows the fraction total emitted light in ϕFF = −30° to ϕFF = 70° (blue dots) and its components with ASM (circles) and SM (crosses) symmetries as a function of r2.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC4493635&req=5

f3: The far-field patterns of the same resonance as Fig. 2.The radius of nanoparticle is r2 = 0 nm (a), 2 nm (b), 4 nm (c), and 7 nm (d). (e) shows the fraction total emitted light in ϕFF = −30° to ϕFF = 70° (blue dots) and its components with ASM (circles) and SM (crosses) symmetries as a function of r2.

Mentions: We then examine the far-field pattern of the resonant mode as a function of particle size to test our analysis. Partial results are shown in Fig. 3. Without the external nanoparticle, the PM shows clear unidirectional emission in the approximate angle range −30o −70o (see Fig. 3(a)). Once the external particle is attached to the circular cavity, the far-field pattern gradually changes. With an increase in particle size from 1 nm to 7 nm, we can observe that the unidirectional emission within the angle range −15°− 45° reduces and the emissions approximately 210°–300° increase quickly. When the particle size r2 is larger than 6 nm, the far-field pattern turns to nearly bi-directional emissions (see the example in Fig. 3(d)).


Single Nanoparticle Detection Using Far-field Emission of Photonic Molecule around the Exceptional Point.

Zhang N, Liu S, Wang K, Gu Z, Li M, Yi N, Xiao S, Song Q - Sci Rep (2015)

The far-field patterns of the same resonance as Fig. 2.The radius of nanoparticle is r2 = 0 nm (a), 2 nm (b), 4 nm (c), and 7 nm (d). (e) shows the fraction total emitted light in ϕFF = −30° to ϕFF = 70° (blue dots) and its components with ASM (circles) and SM (crosses) symmetries as a function of r2.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4493635&req=5

f3: The far-field patterns of the same resonance as Fig. 2.The radius of nanoparticle is r2 = 0 nm (a), 2 nm (b), 4 nm (c), and 7 nm (d). (e) shows the fraction total emitted light in ϕFF = −30° to ϕFF = 70° (blue dots) and its components with ASM (circles) and SM (crosses) symmetries as a function of r2.
Mentions: We then examine the far-field pattern of the resonant mode as a function of particle size to test our analysis. Partial results are shown in Fig. 3. Without the external nanoparticle, the PM shows clear unidirectional emission in the approximate angle range −30o −70o (see Fig. 3(a)). Once the external particle is attached to the circular cavity, the far-field pattern gradually changes. With an increase in particle size from 1 nm to 7 nm, we can observe that the unidirectional emission within the angle range −15°− 45° reduces and the emissions approximately 210°–300° increase quickly. When the particle size r2 is larger than 6 nm, the far-field pattern turns to nearly bi-directional emissions (see the example in Fig. 3(d)).

Bottom Line: In addition to typical mode splitting, we find that the far-field pattern of the PM is significantly changed.Taking a heteronuclear diatomic PM as an example, we demonstrate that a single nanoparticle, whose radius is as small as 1 nm to 7 nm, can be simply monitored through the variation of the far-field pattern.In addition, this research will illuminate new advances in single nanoparticle detection.

View Article: PubMed Central - PubMed

Affiliation: Integrated Nanoscience Lab, Department of Electrical and Information Engineering, Harbin Institute of Technology, Shenzhen, 518055, China.

ABSTRACT
Highly sensitive, label-free detection methods have important applications in fundamental research and healthcare diagnostics. To date, the detection of single nanoparticles has remained largely dependent on extremely precise spectral measurement, which relies on high-cost equipment. Here, we demonstrate a simple but very nontrivial mechanism for the label-free sizing of nanoparticles using the far-field emission of a photonic molecule (PM) around an exceptional point (EP). By attaching a nanoparticle to a PM around an EP, the main resonant behaviors are strongly disturbed. In addition to typical mode splitting, we find that the far-field pattern of the PM is significantly changed. Taking a heteronuclear diatomic PM as an example, we demonstrate that a single nanoparticle, whose radius is as small as 1 nm to 7 nm, can be simply monitored through the variation of the far-field pattern. Compared with conventional methods, our approach is much easier and does not rely on high-cost equipment. In addition, this research will illuminate new advances in single nanoparticle detection.

No MeSH data available.


Related in: MedlinePlus