Lasing mirrorless

S. V. Frolov, M. Ozaki, W. Gellermann, Z. V. Vardeny, K. Yoshino, Mirrorless lasing in conducting polymer poly(2,5-dioclyloxy-p-phenylencvinylcnc) films. Jpn. J. Appl. Phys. 1996, 35, L1371. 

Spectral modes within the narrow peak. However, mode structure was not observed in any of our measurements. Since both ASE and lasing are based on stimulated emission, the difference is not very important in the context of the electrically pumped organic laser. Moreover, because the distinction is not a key issue here, we consider the gain phenomena observed in systems without external feedback to be mirrorless lasing. 

Waveguiding inside the film is crucial mirrorless lasing has not been observed in annealed films of 100 nm thickness, a thickness which is below the cut-off value for waveguiding in this asymmetric layered structure. 

A further confirmation that mirrorless lasing is restricted to single domains comes from an experiment in which an Ooct-OPV5 film has been crystallized from the isotropic melt phase (above 204 °C). Melt crystallization resulted in the formation of large domains with dimensions up to several millimeters (see Fig. 16-29 C). The normalized emission spectra for different excitation energies are shown in Figure 16-47. The excitation spot diameter was 1 mm in these ex-... 

Still relatively unexplored, but potentially a large application field of ordered mesoporous materials is optics and electronics. Marlow et al. succeeded in the synthesis of ordered mesoporous silica fibers doped with a rhodamin laser dye [38]. Upon laser irradiation the waveguide effect reported earlier [27] led to amplification by stimulated emission along the fiber axis. The light emitted from the ends of the fibers was spectrally narrowed and highly directional. The effect observed can be described as a mirrorless lasing which can be useful in the construction of optical circuits. 

Finkehnann H, Kim ST, Munoz A, Palffy Muhoray P, Taheri B. 2001. Tunable mirrorless lasing in cholesteric liquid crystalline elastomers. Adv Mater 13 1069 1072. 

Ozaki M, Kasano M, Ganzke D, Haase W, Yoshino K. 2002. Mirrorless lasing in a dye doped ferroelectric liquid crystal. Adv Mater 14(4) 306 309. 

Processes 1-3 and 5 occur without the necessity of optical feedback (or mirrors), and thus have been termed as mirrorless lasing [111]. Processes 2—5 are also coherent, whereas ASE is not. In addition, processes 2 and 3 are examples of cooperative emission, whereas ASE is a collective emission process. The superradiance process is very. similar to the SF laser action process, except that in superradiance the system is prepared coherently from t= 0, whereas in SF the system evolves in time to be coherent at t > 0 [111]. 

Munoz A, McConney ME, Kosa T, Luchette P, Sukhomlinova L, White TJ, Running TJ, Taheri B (2012) Continuous wave mirrorless lasing in cholesteric liquid crystals with a pitch gradient across the cell gap. Opt Lett 37 2904... 

Moreira M, Relaix S, Cao W, Taheri B, Palffy-Muhoray P (2010) Mirrorless lasing and lasing thresholds in cholesteric liquid crystals. In Blinov LM, Bartolino R (eds) Liquid crystal microlasers. Transworld Research Network, Kerala, p 223. 

Yanagi, A. Yoshiki, S. Hotta and S. Kobayashi, Mirrorless lasing from thiophene/phenylene co-oligomer crystals based on stimulated resonance Raman scattering, j. Appl. Phys., 96, 4240-4244 (2004) with permission from the American Institute of Physics... 

Alvarez E, He M, Munoz AF, Palffy-Muhoray P, Serak SV, Taheri B, Twieg R (2001) Mirrorless lasing and energy transfer in cholesteric liquid crystals doped with laser dyes. Mol Cryst Liq Cryst 57 369... 

D. Wenzlik, Liquid Crystalline Cellulose Derivatives for Mirrorless Lasing, Dissertation,... 

B. F., Buratto, S.K., and Stucky, G.D. (2000) Mirrorless lasing from mesostructured waveguides patterned by soft lithography. Science, 287,... 

Because of the combined influence of the alignment and pitch of the helical modulation in different states, the material acquires a photonic band gap. The self assembled bio-derived photonic crystals thus have attractive optical properties for which CNC films are considered for development of newer materials for novel application. Especially the helical arrangement of the nanorods, converts these to materials with higher application potential in the field of optoelectronics. Such kind of films has attractive optical properties and possibly can be used in applications such as security papers and mirrorless lasing. Biological nanomaterials are also biodegradable. 

Yoon, J., Lee, W., Caruge, J.-M., Bawendi, M., Thoms, E. L., Kooi, S., and Prasad, P. N. 2006. Defectmode mirrorless lasing in dye-doped organic/inorganic hybrid one-dimensional photonic crystal. Appl. Phys. Lett. 88 091102. 

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