Abstract

The photothermal properties and heat diffusion of polymeric lasers, made up from solutions of Rhodamine 6G in solid matrices of poly(2-hydroxyethyl methacrylate) with different amounts of the cross-linking monomer ethylene glycol dimethacrylate and copolymers of 2-hydroxyethyl methacrylate and methyl methacrylate have been studied through photothermal deflection spectroscopy. The heat load that is due to the pumping process was quantified as a function of the pump excitation repetition frequency (0.25–10 Hz), determining the time-dependent temperature changes at different locations within the laser matrix. A theoretical model, which reproduces these changes with high accuracy, was developed on the basis of the heat-diffusion equation of optically dense fluids. The observed thermal effects became important for impairing the laser stability at pump repetition frequencies higher than 1 Hz. In addition, the irreversible optical changes produced in the laser matrices at high pump fluence values (>1 J/cm2) were also analyzed. These effects originate, most likely, from a two-step photothermal mechanism.

© 2003 Optical Society of America

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References

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    [CrossRef]
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    [CrossRef]
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    [CrossRef]
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    [CrossRef]
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    [CrossRef]
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    [CrossRef]
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    [CrossRef]
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    [CrossRef]
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    [CrossRef]
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    [CrossRef]
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    [CrossRef]
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    [CrossRef] [PubMed]
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    [CrossRef]

2001 (1)

S. Nonel, C. Martí, I. García-Moreno, A. Costela, R. Sastre, “Opto-acoustic study of Tinuvin-P and Rhodamine 6G in solid polymeric matrices,” Appl. Phys. B 72, 355–360 (2001).
[CrossRef]

2000 (1)

1999 (3)

F. J. Duarte, “Multiple-prism grating solid-state dye laser oscillator: optimized architecture,” App. Opt. 38, 6347–6349 (1999).
[CrossRef]

S. M. Giffin, W. J. Wadsworth, A. D. Woolhouse, G. J. Smith, T. G. Haskell, “Efficient, high photostability, high brightness, co-polymer solid dye lasers,” J. Mod. Opt. 46, 1941–1945 (1999).
[CrossRef]

M. Ahmad, M. D. Rahn, T. A. King, “Singlet oxygen and dye-triplet-state quenching in solid dye lasers consisting of Pyrromethene 567-doped poly(methyl methacrylate),” Appl. Opt. 38, 6337–6342 (1999).
[CrossRef]

1998 (2)

1997 (1)

1996 (1)

A. Costela, I. García-Moreno, J. M. Figuera, F. Amat-Guerri, J. Barroso, R. Sastre, “Solid-state dye laser based on Coumarin 540A-doped polymeric matrices,” Opt. Commun. 130, 44–50 (1996).
[CrossRef]

1995 (1)

A. Costela, F. Florido, I. Garcia-Moreno, R. Duchowicz, F. Amat-Guerri, J. M. Figuera, R. Sastre, “Solid-state dye lasers based on copolymers of 2-hydroxyethyl methacrylate and methyl methacrylate doped with Rhodamine 6G,” Appl. Phys. B 60, 383–389 (1995).
[CrossRef]

1994 (1)

F. J. Duarte, “Solid-state multiple-prism grating dye-laser oscillators,” App. Opt. 33, 3857–3860 (1994).
[CrossRef]

1993 (2)

F. Amat Guerri, A. Costela, J. M. Figuera, F. Florido, R. Sastre, “Laser action from Rhodamine 6G-doped poly(2-hydroxyethyl methacrylate) matrices with different crosslinking degrees,” Chem. Phys. Lett. 209, 352–356 (1993).
[CrossRef]

U. Narang, F. V. Bright, P. N. Prasad, “Characterization of Rhodamine 6G-doped thin sol-gel films,” Appl. Spectrosc. 47, 229–234 (1993).
[CrossRef]

1992 (1)

Acuña, A. U.

Ahmad, M.

Amat Guerri, F.

F. Amat Guerri, A. Costela, J. M. Figuera, F. Florido, R. Sastre, “Laser action from Rhodamine 6G-doped poly(2-hydroxyethyl methacrylate) matrices with different crosslinking degrees,” Chem. Phys. Lett. 209, 352–356 (1993).
[CrossRef]

Amat-Guerri, F.

A. Costela, I. García-Moreno, J. M. Figuera, F. Amat-Guerri, J. Barroso, R. Sastre, “Solid-state dye laser based on Coumarin 540A-doped polymeric matrices,” Opt. Commun. 130, 44–50 (1996).
[CrossRef]

A. Costela, F. Florido, I. Garcia-Moreno, R. Duchowicz, F. Amat-Guerri, J. M. Figuera, R. Sastre, “Solid-state dye lasers based on copolymers of 2-hydroxyethyl methacrylate and methyl methacrylate doped with Rhodamine 6G,” Appl. Phys. B 60, 383–389 (1995).
[CrossRef]

Barroso, J.

A. Costela, I. García-Moreno, J. M. Figuera, F. Amat-Guerri, J. Barroso, R. Sastre, “Solid-state dye laser based on Coumarin 540A-doped polymeric matrices,” Opt. Commun. 130, 44–50 (1996).
[CrossRef]

Bright, F. V.

Costela, A.

S. Nonel, C. Martí, I. García-Moreno, A. Costela, R. Sastre, “Opto-acoustic study of Tinuvin-P and Rhodamine 6G in solid polymeric matrices,” Appl. Phys. B 72, 355–360 (2001).
[CrossRef]

R. Duchowicz, L. B. Scaffardi, A. Costela, I. García-Moreno, R. Sastre, A. U. Acuña, “Photothermal characterization and stability analysis of polymeric dye lasers,” Appl. Opt. 39, 4959–4963 (2000).

A. Costela, I. García-Moreno, J. M. Figuera, F. Amat-Guerri, J. Barroso, R. Sastre, “Solid-state dye laser based on Coumarin 540A-doped polymeric matrices,” Opt. Commun. 130, 44–50 (1996).
[CrossRef]

A. Costela, F. Florido, I. Garcia-Moreno, R. Duchowicz, F. Amat-Guerri, J. M. Figuera, R. Sastre, “Solid-state dye lasers based on copolymers of 2-hydroxyethyl methacrylate and methyl methacrylate doped with Rhodamine 6G,” Appl. Phys. B 60, 383–389 (1995).
[CrossRef]

F. Amat Guerri, A. Costela, J. M. Figuera, F. Florido, R. Sastre, “Laser action from Rhodamine 6G-doped poly(2-hydroxyethyl methacrylate) matrices with different crosslinking degrees,” Chem. Phys. Lett. 209, 352–356 (1993).
[CrossRef]

A. Costela, I. García-Moreno, R. Sastre, “Materials for solid-state dye lasers,” in Handbook of Advanced Electronic and Photonic Materials, H. S. Nalwa, ed., (Academic, San Diego, 2001), Vol. 7, Chap. 4.
[CrossRef]

Duarte, F. J.

F. J. Duarte, “Multiple-prism grating solid-state dye laser oscillator: optimized architecture,” App. Opt. 38, 6347–6349 (1999).
[CrossRef]

F. J. Duarte, “Solid-state multiple-prism grating dye-laser oscillators,” App. Opt. 33, 3857–3860 (1994).
[CrossRef]

Duchowicz, R.

R. Duchowicz, L. B. Scaffardi, A. Costela, I. García-Moreno, R. Sastre, A. U. Acuña, “Photothermal characterization and stability analysis of polymeric dye lasers,” Appl. Opt. 39, 4959–4963 (2000).

A. Costela, F. Florido, I. Garcia-Moreno, R. Duchowicz, F. Amat-Guerri, J. M. Figuera, R. Sastre, “Solid-state dye lasers based on copolymers of 2-hydroxyethyl methacrylate and methyl methacrylate doped with Rhodamine 6G,” Appl. Phys. B 60, 383–389 (1995).
[CrossRef]

Dyumaev, K. M.

Figuera, J. M.

A. Costela, I. García-Moreno, J. M. Figuera, F. Amat-Guerri, J. Barroso, R. Sastre, “Solid-state dye laser based on Coumarin 540A-doped polymeric matrices,” Opt. Commun. 130, 44–50 (1996).
[CrossRef]

A. Costela, F. Florido, I. Garcia-Moreno, R. Duchowicz, F. Amat-Guerri, J. M. Figuera, R. Sastre, “Solid-state dye lasers based on copolymers of 2-hydroxyethyl methacrylate and methyl methacrylate doped with Rhodamine 6G,” Appl. Phys. B 60, 383–389 (1995).
[CrossRef]

F. Amat Guerri, A. Costela, J. M. Figuera, F. Florido, R. Sastre, “Laser action from Rhodamine 6G-doped poly(2-hydroxyethyl methacrylate) matrices with different crosslinking degrees,” Chem. Phys. Lett. 209, 352–356 (1993).
[CrossRef]

Florido, F.

A. Costela, F. Florido, I. Garcia-Moreno, R. Duchowicz, F. Amat-Guerri, J. M. Figuera, R. Sastre, “Solid-state dye lasers based on copolymers of 2-hydroxyethyl methacrylate and methyl methacrylate doped with Rhodamine 6G,” Appl. Phys. B 60, 383–389 (1995).
[CrossRef]

F. Amat Guerri, A. Costela, J. M. Figuera, F. Florido, R. Sastre, “Laser action from Rhodamine 6G-doped poly(2-hydroxyethyl methacrylate) matrices with different crosslinking degrees,” Chem. Phys. Lett. 209, 352–356 (1993).
[CrossRef]

Garcia-Moreno, I.

A. Costela, F. Florido, I. Garcia-Moreno, R. Duchowicz, F. Amat-Guerri, J. M. Figuera, R. Sastre, “Solid-state dye lasers based on copolymers of 2-hydroxyethyl methacrylate and methyl methacrylate doped with Rhodamine 6G,” Appl. Phys. B 60, 383–389 (1995).
[CrossRef]

García-Moreno, I.

S. Nonel, C. Martí, I. García-Moreno, A. Costela, R. Sastre, “Opto-acoustic study of Tinuvin-P and Rhodamine 6G in solid polymeric matrices,” Appl. Phys. B 72, 355–360 (2001).
[CrossRef]

R. Duchowicz, L. B. Scaffardi, A. Costela, I. García-Moreno, R. Sastre, A. U. Acuña, “Photothermal characterization and stability analysis of polymeric dye lasers,” Appl. Opt. 39, 4959–4963 (2000).

A. Costela, I. García-Moreno, J. M. Figuera, F. Amat-Guerri, J. Barroso, R. Sastre, “Solid-state dye laser based on Coumarin 540A-doped polymeric matrices,” Opt. Commun. 130, 44–50 (1996).
[CrossRef]

A. Costela, I. García-Moreno, R. Sastre, “Materials for solid-state dye lasers,” in Handbook of Advanced Electronic and Photonic Materials, H. S. Nalwa, ed., (Academic, San Diego, 2001), Vol. 7, Chap. 4.
[CrossRef]

Giffin, S. M.

S. M. Giffin, W. J. Wadsworth, A. D. Woolhouse, G. J. Smith, T. G. Haskell, “Efficient, high photostability, high brightness, co-polymer solid dye lasers,” J. Mod. Opt. 46, 1941–1945 (1999).
[CrossRef]

Gupta, R.

Haskell, T. G.

S. M. Giffin, W. J. Wadsworth, A. D. Woolhouse, G. J. Smith, T. G. Haskell, “Efficient, high photostability, high brightness, co-polymer solid dye lasers,” J. Mod. Opt. 46, 1941–1945 (1999).
[CrossRef]

He, Q.

King, T. A.

Manenkov, A. A.

Martí, C.

S. Nonel, C. Martí, I. García-Moreno, A. Costela, R. Sastre, “Opto-acoustic study of Tinuvin-P and Rhodamine 6G in solid polymeric matrices,” Appl. Phys. B 72, 355–360 (2001).
[CrossRef]

Maslyukov, A. P.

Matyushin, G. A.

Narang, U.

Nechitailo, V. S.

Ng, S. W.

Nonel, S.

S. Nonel, C. Martí, I. García-Moreno, A. Costela, R. Sastre, “Opto-acoustic study of Tinuvin-P and Rhodamine 6G in solid polymeric matrices,” Appl. Phys. B 72, 355–360 (2001).
[CrossRef]

Popov, S.

Prasad, P. N.

Prokhorov, A. M.

Przhonska, O. V.

O. V. Przhonska, “Optical properties and applications of near infrared dyes in polymeric media,” Near-Infrared Dyes for High Technology Applications, H. S. Daehne, U. Resch, O. Wolfbeis, eds. (Kluwer Academic, Dordrecht, The Netherlands, 1998), pp. 265–285.
[CrossRef]

Rahn, M. D.

Sastre, R.

S. Nonel, C. Martí, I. García-Moreno, A. Costela, R. Sastre, “Opto-acoustic study of Tinuvin-P and Rhodamine 6G in solid polymeric matrices,” Appl. Phys. B 72, 355–360 (2001).
[CrossRef]

R. Duchowicz, L. B. Scaffardi, A. Costela, I. García-Moreno, R. Sastre, A. U. Acuña, “Photothermal characterization and stability analysis of polymeric dye lasers,” Appl. Opt. 39, 4959–4963 (2000).

A. Costela, I. García-Moreno, J. M. Figuera, F. Amat-Guerri, J. Barroso, R. Sastre, “Solid-state dye laser based on Coumarin 540A-doped polymeric matrices,” Opt. Commun. 130, 44–50 (1996).
[CrossRef]

A. Costela, F. Florido, I. Garcia-Moreno, R. Duchowicz, F. Amat-Guerri, J. M. Figuera, R. Sastre, “Solid-state dye lasers based on copolymers of 2-hydroxyethyl methacrylate and methyl methacrylate doped with Rhodamine 6G,” Appl. Phys. B 60, 383–389 (1995).
[CrossRef]

F. Amat Guerri, A. Costela, J. M. Figuera, F. Florido, R. Sastre, “Laser action from Rhodamine 6G-doped poly(2-hydroxyethyl methacrylate) matrices with different crosslinking degrees,” Chem. Phys. Lett. 209, 352–356 (1993).
[CrossRef]

A. Costela, I. García-Moreno, R. Sastre, “Materials for solid-state dye lasers,” in Handbook of Advanced Electronic and Photonic Materials, H. S. Nalwa, ed., (Academic, San Diego, 2001), Vol. 7, Chap. 4.
[CrossRef]

Scaffardi, L. B.

Smith, G. J.

S. M. Giffin, W. J. Wadsworth, A. D. Woolhouse, G. J. Smith, T. G. Haskell, “Efficient, high photostability, high brightness, co-polymer solid dye lasers,” J. Mod. Opt. 46, 1941–1945 (1999).
[CrossRef]

Tou, T. Y.

Vyas, R.

Wadsworth, W. J.

S. M. Giffin, W. J. Wadsworth, A. D. Woolhouse, G. J. Smith, T. G. Haskell, “Efficient, high photostability, high brightness, co-polymer solid dye lasers,” J. Mod. Opt. 46, 1941–1945 (1999).
[CrossRef]

Woolhouse, A. D.

S. M. Giffin, W. J. Wadsworth, A. D. Woolhouse, G. J. Smith, T. G. Haskell, “Efficient, high photostability, high brightness, co-polymer solid dye lasers,” J. Mod. Opt. 46, 1941–1945 (1999).
[CrossRef]

Yee, K. C.

App. Opt. (2)

F. J. Duarte, “Solid-state multiple-prism grating dye-laser oscillators,” App. Opt. 33, 3857–3860 (1994).
[CrossRef]

F. J. Duarte, “Multiple-prism grating solid-state dye laser oscillator: optimized architecture,” App. Opt. 38, 6347–6349 (1999).
[CrossRef]

Appl. Opt. (5)

Appl. Phys. B (2)

S. Nonel, C. Martí, I. García-Moreno, A. Costela, R. Sastre, “Opto-acoustic study of Tinuvin-P and Rhodamine 6G in solid polymeric matrices,” Appl. Phys. B 72, 355–360 (2001).
[CrossRef]

A. Costela, F. Florido, I. Garcia-Moreno, R. Duchowicz, F. Amat-Guerri, J. M. Figuera, R. Sastre, “Solid-state dye lasers based on copolymers of 2-hydroxyethyl methacrylate and methyl methacrylate doped with Rhodamine 6G,” Appl. Phys. B 60, 383–389 (1995).
[CrossRef]

Appl. Spectrosc. (1)

Chem. Phys. Lett. (1)

F. Amat Guerri, A. Costela, J. M. Figuera, F. Florido, R. Sastre, “Laser action from Rhodamine 6G-doped poly(2-hydroxyethyl methacrylate) matrices with different crosslinking degrees,” Chem. Phys. Lett. 209, 352–356 (1993).
[CrossRef]

J. Mod. Opt. (1)

S. M. Giffin, W. J. Wadsworth, A. D. Woolhouse, G. J. Smith, T. G. Haskell, “Efficient, high photostability, high brightness, co-polymer solid dye lasers,” J. Mod. Opt. 46, 1941–1945 (1999).
[CrossRef]

J. Opt. Soc. Am. B (1)

Opt. Commun. (1)

A. Costela, I. García-Moreno, J. M. Figuera, F. Amat-Guerri, J. Barroso, R. Sastre, “Solid-state dye laser based on Coumarin 540A-doped polymeric matrices,” Opt. Commun. 130, 44–50 (1996).
[CrossRef]

Other (3)

A. Costela, I. García-Moreno, R. Sastre, “Materials for solid-state dye lasers,” in Handbook of Advanced Electronic and Photonic Materials, H. S. Nalwa, ed., (Academic, San Diego, 2001), Vol. 7, Chap. 4.
[CrossRef]

J. Brandrup, E. H. Immergut, eds., Polymer Handbook (Wiley, New York, 1975).

O. V. Przhonska, “Optical properties and applications of near infrared dyes in polymeric media,” Near-Infrared Dyes for High Technology Applications, H. S. Daehne, U. Resch, O. Wolfbeis, eds. (Kluwer Academic, Dordrecht, The Netherlands, 1998), pp. 265–285.
[CrossRef]

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Figures (8)

Fig. 1
Fig. 1

Experimental setup of the near-collinear photothermal deflection technique including focusing lenses (L1 and L2), interferential filter (IF), position detector (PD), and personal computer (PC).

Fig. 2
Fig. 2

Experimental photothermal deflection signals (ϕ), in arbitrary units, at two pump repetition rates (f), for samples of P(HEMA-EGDMA) 50% (v:v), excited at 532 nm with 8-mJ pulse energy. (a) f = 0.9 Hz and (b) f = 3.3 Hz. Overlaid is the continuous curve corresponding to the theoretical results of the model developed in the main text [Eq. (6)]. Inset: an amplified view of trace (b).

Fig. 3
Fig. 3

Maximum amplitude of the photothermal signal in the steady-state (S max) as a function of the composition of a laser matrix of P(HEMA-EGDMA) for different pump rates: filled circles, 0.77; open squares, 1.42; triangles, 2.5; inverse triangles, 3.33; open circles, 5; and filled squares, 10 Hz. Inset: the change in the deflection signal relative to that registered at the lowest pump rate (S max,k /S 0,k ) as a function of the pump rate and for each sample composition.

Fig. 4
Fig. 4

Temperature measurement scheme: Δd is the minor distance between the central excitation spot and the thermocouple, and s defines the thermocouple position.

Fig. 5
Fig. 5

Experimental temperature evolution within a laser rod as function of time, as detected by a thermocouple located at Δd = 0.8 mm and s = 0 from the excitation spot. The overlaid continuous curve is the theoretical prediction by use of Eq. (1). Matrix composition P(HEMA-EGDMA), 50% (v:v), 2 × 10-3 M Rh6G; pump repetition rate, 5 Hz. The excitation laser was turned off after 30 s of operation.

Fig. 6
Fig. 6

Temperature profiles within a laser rod, as measured with a thermocouple (points) at different positions (s) and as computed (curves) with the theoretical model developed in the main text, for the same positions. The data correspond to 10 (triangles), 20 (filled squares), 30 (open circles), 40 (open squares), and 50 (filled circles) s from the start of a pulse train of ∼150 pump pulses, with a 5-Hz repetition rate. Dashed curve corresponds to the predicted temperature change for a single pump excitation pulse. Thermocouple position Δd = 1.6 mm. Matrix composition: P(HEMA-EGDMA), 50% (v:v), 2 × 10-3 M Rh6G.

Fig. 7
Fig. 7

PTDS signal for a sequential series of excitation pulse trains with different repetition rates, with a fluence of 1.5 J/cm2. A new residual deflection signal (background) can be observed, which persists between two consecutive pulse trains. Matrix composition P(HEMA-MMA), 50:50 (v:v), 2 × 10-3 M Rh6G.

Fig. 8
Fig. 8

Irreversible photothermal deflection background increment (ΔS) as a function of the number of pump pulses N p for different compositions of a P(HEMA-EGDMA) matrix, at a pump fluence of 1.5 J/cm2. EGDMA fraction: 0% (inverse triangles), 10% (open squares), 15% (filled triangles), 20% (filled circles), 30% (open triangles), and 50% (open circles). Inset: the slope of the linear fits, ΔS/ N p , as a function of the fraction of the EGDMA cross-linking agent.

Equations (10)

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

Tx, y, z, t=αE0πρCpexp-2x2+y2/a2+8Dta2+8Dt×expααDt-zerfc2αDt-z4Dt for t>t0,
ϕy= nx, y, z, t/y ds.
ϕy=1n0nTpathTx, y, z, tyds,
nx, y, z, t=n0+nTTx, y, z, t.
Φit=Φi-1+A di-1a2+8Dt2exp-2di-12a2+8Dt×lmexpααDt-zerfc2αDt-z/4Dt1/21+Φi-121/2,
A=-1n0nT4αE0πρCp.
di=di-1+dz dz=di-1+lm Φi.
TN=j=0N Yt-jΔtTt-jΔt,
φN,it=j=1N Yt-jΔtΦj,it-jΔt,
Yt=1if t>t0,0otherwise.

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