Abstract

We reveal that the overall evanescent wave (EW) power captured by an unclad multimode fiber employed in a sensing configuration is determined by the tunneling modes, not the guided modes. While enormous in strength, most of this power is inaccessible using traditional EW power enhancers. However, we found that by roughening the fiber end face, this supposedly lost power can be recaptured and thus can boost the detectable power level significantly. Intensive mode mixing events across various mode categories are proposed to interpret the observed phenomenon.

© 2011 Optical Society of America

Full Article  |  PDF Article

References

  • View by:
  • |
  • |
  • |

  1. J. P. Golden, G. P. Anderson, S. Y. Rabbany, and F. S. Ligler, IEEE Trans. Biomed. Eng. 41, 585 (1994).
    [CrossRef]
  2. B. D. MacCraith, C. McDonagh, A. K. McEvoy, T. Butler, G. O’Keeffe, and V. Murphy, J. Sol-Gel Sci. Technol. 8, 1053 (1997).
    [CrossRef]
  3. J. Ma, W. J. Bock, and A. Cusano, Opt. Express 17, 7630(2009).
    [CrossRef] [PubMed]
  4. A. W. Snyder and J. D. Love, Optical Waveguide Theory (Chapman & Hall, 1983).
  5. D. Gloge, Appl. Opt. 10, 2252 (1971).
    [CrossRef] [PubMed]
  6. J. Ma and W. J. Bock, Opt. Lett. 32, 8 (2007).
    [CrossRef]

2009 (1)

2007 (1)

1997 (1)

B. D. MacCraith, C. McDonagh, A. K. McEvoy, T. Butler, G. O’Keeffe, and V. Murphy, J. Sol-Gel Sci. Technol. 8, 1053 (1997).
[CrossRef]

1994 (1)

J. P. Golden, G. P. Anderson, S. Y. Rabbany, and F. S. Ligler, IEEE Trans. Biomed. Eng. 41, 585 (1994).
[CrossRef]

1971 (1)

Anderson, G. P.

J. P. Golden, G. P. Anderson, S. Y. Rabbany, and F. S. Ligler, IEEE Trans. Biomed. Eng. 41, 585 (1994).
[CrossRef]

Bock, W. J.

Butler, T.

B. D. MacCraith, C. McDonagh, A. K. McEvoy, T. Butler, G. O’Keeffe, and V. Murphy, J. Sol-Gel Sci. Technol. 8, 1053 (1997).
[CrossRef]

Cusano, A.

Gloge, D.

Golden, J. P.

J. P. Golden, G. P. Anderson, S. Y. Rabbany, and F. S. Ligler, IEEE Trans. Biomed. Eng. 41, 585 (1994).
[CrossRef]

Ligler, F. S.

J. P. Golden, G. P. Anderson, S. Y. Rabbany, and F. S. Ligler, IEEE Trans. Biomed. Eng. 41, 585 (1994).
[CrossRef]

Love, J. D.

A. W. Snyder and J. D. Love, Optical Waveguide Theory (Chapman & Hall, 1983).

Ma, J.

MacCraith, B. D.

B. D. MacCraith, C. McDonagh, A. K. McEvoy, T. Butler, G. O’Keeffe, and V. Murphy, J. Sol-Gel Sci. Technol. 8, 1053 (1997).
[CrossRef]

McDonagh, C.

B. D. MacCraith, C. McDonagh, A. K. McEvoy, T. Butler, G. O’Keeffe, and V. Murphy, J. Sol-Gel Sci. Technol. 8, 1053 (1997).
[CrossRef]

McEvoy, A. K.

B. D. MacCraith, C. McDonagh, A. K. McEvoy, T. Butler, G. O’Keeffe, and V. Murphy, J. Sol-Gel Sci. Technol. 8, 1053 (1997).
[CrossRef]

Murphy, V.

B. D. MacCraith, C. McDonagh, A. K. McEvoy, T. Butler, G. O’Keeffe, and V. Murphy, J. Sol-Gel Sci. Technol. 8, 1053 (1997).
[CrossRef]

O’Keeffe, G.

B. D. MacCraith, C. McDonagh, A. K. McEvoy, T. Butler, G. O’Keeffe, and V. Murphy, J. Sol-Gel Sci. Technol. 8, 1053 (1997).
[CrossRef]

Rabbany, S. Y.

J. P. Golden, G. P. Anderson, S. Y. Rabbany, and F. S. Ligler, IEEE Trans. Biomed. Eng. 41, 585 (1994).
[CrossRef]

Snyder, A. W.

A. W. Snyder and J. D. Love, Optical Waveguide Theory (Chapman & Hall, 1983).

Appl. Opt. (1)

IEEE Trans. Biomed. Eng. (1)

J. P. Golden, G. P. Anderson, S. Y. Rabbany, and F. S. Ligler, IEEE Trans. Biomed. Eng. 41, 585 (1994).
[CrossRef]

J. Sol-Gel Sci. Technol. (1)

B. D. MacCraith, C. McDonagh, A. K. McEvoy, T. Butler, G. O’Keeffe, and V. Murphy, J. Sol-Gel Sci. Technol. 8, 1053 (1997).
[CrossRef]

Opt. Express (1)

Opt. Lett. (1)

Other (1)

A. W. Snyder and J. D. Love, Optical Waveguide Theory (Chapman & Hall, 1983).

Cited By

OSA participates in CrossRef's Cited-By Linking service. Citing articles from OSA journals and other participating publishers are listed here.

Alert me when this article is cited.


Figures (4)

Fig. 1
Fig. 1

Three traditional fiber-optic EW platforms that fail to access I E W ( ) : (a) fiber taper, (b) sol–gel overlay, (c) U-shaped segment. I E is the excitation power and I R is the received EW power after exiting from the clad fiber.

Fig. 2
Fig. 2

Dependence of EW power collection on the mode groups. (a) Clad fiber with an unclad segment showing permitted mode groups and penetration depths. (b) Histogram showing mode populations and EW power for associated segments.

Fig. 3
Fig. 3

Fiber-optic EW sensing platform to demonstrate the enhancer based on a roughened end face. A liquid droplet of R6G water solution represents the fluorescence-capable sample.

Fig. 4
Fig. 4

Experimental results for the roughened fiber end face A and flat end face B.

Equations (21)

Equations on this page are rendered with MathJax. Learn more.

I S totl = I E W 0 ( + ) + I E W 0 ( ) = 2 × I E W 0 ( ± ) .
N t N g = V 2 / 2 = π 2 d 2 ( n co 2 n cl 2 ) / 2 λ 2 ,
N g , t cl 40 % N g , t lq .
Δ lq N g = 1.5 N g cl and Δ lq N t = 1.5 N t cl .
δ g _ i lq > δ g _ j cl and δ t _ k lq > δ t _ l cl , i Δ lq N g , j N g cl , k Δ lq N t , l N t cl .
I R I E W 0 ( + ) ,
I E W 0 ( ± ) = I h , t lq ( ± ) ,
I S totl = 2 × I h , t lq ( ± ) .
I S 1 < I E W 0 ( ) = I h , t lq ( ) .
N h 2 , t 2 , t 3 lq = Δ lq N g + Δ lq N t > > N h 1 , t 1 cl , and δ h 2 _ i lq > δ h 1 _ j cl , δ ( t 2 , t 3 ) _ k lq > δ t 1 _ l cl , i N h 2 lq , j N h 1 cl , k N t 2 , t 3 lq , l N t 1 cl .
I R = I h 1 , t 1 cl ( + ) k I k lq ( ) , k = h 2 , t 2 , t 3.
I i lq ( + ) I i lq ( ) , i = h 1 , t 1 , h 2 , t 2 , t 3 ,
I j lq ( ± ) I j cl ( + ) , j = h 1 , t 1.
I S totl = 2 × i I i lq ( + ) , i = h 1 , t 1 , h 2 , t 2 , t 3.
I S 1 = k I k lq ( ) < 50 % I S totl , k = h 1 , t 1 , h 2 , t 2 ,
I R 50 % I S totl .
I R < 9 % I t 3 lq ( + ) ,
I R I S 1 I h 2 , t 2 lq .
Δ lq N t > Δ lq N h 2 .
δ t _ i lq > δ h 2 _ j lq , i Δ lq N t , j Δ lq N h 2 .
I F lq ( ± ) = i I i lq ( + ) = 50 % I S totl , i = h 1 , t 1 , h 2 , t 2 , t 3.

Metrics