Cynllunio 'Laser Tonfedd Ddeuol'


Cynllunio 'Laser Tonfedd Ddeuol'
Daniel Roberts ac Iestyn Pierce

Mae’r gwaith hwn yn seiliedig ar y syniad o gynllunio laser â’r gallu i daflu golau ar ddwy donfedd wahanol yr un pryd. Mae laser o’r math hwn wedi cael ei gynllunio yn y gorffennol, ond roedd y gwahaniaeth rhwng y ddwy donfedd ar raddfa lawer mwy. Bwriedir lleihau’r gwahaniaeth hwn, ond byddwn yn dal i fedru cael y laser i allyrru gan ddefnyddio dwy donfedd ar wahân. Bydd effaith ehangu lled y llinell hefyd yn cael ei ystyried, gan ei bod yn bwysig edrych ar y pellter rhwng y ddwy donfedd cyn eu bod yn ymddangos yn un brig llydan yn y sbectrwm, yn hytrach na dau frig cul. Bydd y pellter hwn yn cael ei fesur er mwyn sefydlu terfyn ar gyfer y gwahaniad mwyaf posibl rhwng y ddwy donfedd lle na fyddai’n bosibl gweld dwy linell gydrannol yn y sbectrwm. Bydd gwneud hyn yn galluogi dylunio ‘laser tonfedd ddeuol’ ag amrediad o wahaniaethau o ran tonfedd, a fydd yn arwain at y posibilrwydd o greu ymbelydredd teraherts o un laser, yn hytrach na ‘chymysgu’ y golau o ddau laser gwahanol gyda’i gilydd, fel a wnaed yn y gorffennol.


Cyfeiriad:

 
  	Daniel Roberts ac Iestyn Pierce, ‘Cynllunio “Laser Tonfedd Ddeuol”’, Gwerddon, 22, Hydref 2016, 75–93.
   

Allweddeiriau

 
    Laser, VCSEL, VECSEL, terahertz, tonfedd ddeuol, lled-llinell, electroneg, Leinonen, Schawlow-Townes, Charles Henry.
    

Llyfryddiaeth:

 
  	
  1. Badilita, V., Carlin, J. F., Ilegems, M., et al. (2004), ‘Rate-equation model for coupledcavity surface-emitting lasers’, IEEE Journal of Quantum Electronics, 40 (12), 1646–56.
  2. Carlin, J. F., Stanley, R. P., Pellandini, P., et al. (1999), ‘The dual wavelength bi-vertical cavity surface emitting laser’, Applied Physics Letters, 75 (7) 908–10.
  3. Coldren, L. A. a Corzine, S. W. (1995), Diode Lasers and Photonic Integrated Circuits (New York: Wiley).
  4. Fan, L., Fallahi, M., Hader, J., et al. (2007), ‘Linearly polarized dual-wavelength verticalexternal-cavity surface-emitting laser’, Applied Physics Letters, 90 (18), 181124-1–3.
  5. Geske, J., Gan, K. G., Okuno, Y. L., et al. (2004), ‘Vertical-cavity surface-emitting laser active regions for enhanced performance with optical pumping’, IEEE Journal of Quantum Electronics, 40 (9), 1155–62.
  6. Grasso, D. M., a Choquette, K. D. (2003), ‘Threshold and modal characteristics of composite-resonator vertical-cavity lasers’, IEEE Journal of Quantum Electronics, 39 (12), 1526–30.
  7. Hakki, B. (1980), ‘Optical and microwave instabilities in injection lasers’, IEEE Journal of Applied Physics, 51 (1) 68–73.
  8. Henry, C. H. (1982), ‘Theory of the linewidth of semiconductor lasers’, IEEE Journal of Quantum Electronics, 18 (2), 259–64.
  9. Henry, C. H. (1983), ‘Theory of the phase noise and power spectrum of a single mode injection laser’, IEEE Journal of Quantum Electronics, 19 (9), 1391–97.
  10. Hessenius, C., Lukowski, M., a Fallahi, M. (2012), ‘High-power tunable two-wavelength generation in a two chip co-linear t-cavity vertical external cavity surface-emitting laser’, IEEE Applied Physics Letters, 101, 12, 121110-1–3.
  11. Hidaka, T., a Hatano, Y. (1991), ‘Simultaneous two wave oscillation LD using biperiodic binary grating’, IEEE Electronics Letters, 27, 12, 1075–6.
  12. Kitaeva, G. (2008), ‘Terahertz generation by means of optical lasers’, Laser Physics Letters, 5 (8), 559–76.
  13. Leinonen, T., Morozov, Y. A., Härkönen, A., et al. (2005), ‘Vertical External-Cavity Surface-Emitting Laser for Dual-Wavelength Generation’, IEEE Photonics Technology Letters, 17 (12), 2508–10.
  14. Lin, C. F., Chen, M. J. a Lee, B. L. (1998), ‘Wide-range tunable dual-wavelength semiconductor laser using asymmetric dual quantum wells’, IEEE Photonics Technology Letters, 10 (9), 1208–10.
  15. Lax, M. (1967), ‘Classical noise V. Noise in self-sustained oscillators’, Physical Review, 160, 290.
  16. Morozov, Y. A., a Morozov, M. Y. (2013), ‘Intracavity Nonlinear Frequency Down-Conversion in a Continuous-Wave Operation Regime of a Dual-Wavelength Vertical-External-Cavity Surface-Emitting Laser’, IEEE Journal of Quantum Electronics, 19 (5), 1702105-1–5.
  17. Osinksi, M., a Buus, J. (1987), ‘Linewidth broadening factor in semiconductor lasers – an overview’, IEEE Journal of Quantum Electronics, 23 (1), 9–29.
  18. Pal, V., Trofimoff, P., Miranda, B. X., et al. (2010), ‘Measurement of the coupling constant in a two-frequency VECSEL’, Optics Express, 18 (5), 5008–14.
  19. Paschotta, R. (2008), ‘Schawlow–Townes Linewidth’, yn Paschotta, R. (gol.), Encyclopaedia of Laser Physics and Technology, argraffiad 1af (Berlin: Wiley-VHC), t. 655.
  20. Pellandini, P., Stanley, R. P., Houdre, R., et al. (1997), ‘Dual-Wavelength laser emission from a coupled semiconductor micro-cavity’, Applied Physics Letters, 71 (7), 864–6.
  21. Poguntke, K., Soole, J. B. D., Scherer, A., et al. (1993), ‘Simultaneous multiple wavelength operation of a multistripe array grating integrated cavity laser’, Applied Physics Letters, 62, (17), 2024–6.
  22. Saeedkia, D., Mansour, R. R. a Safavi-Naeini, S. (2005), ‘Analysis and design of a continuous-wave terahertz photoconductive photomixer array source’, IEEE Transactions, Antennas and Propagation, 53 (12), 4044–50.
  23. Schawlow, A. L. a Townes, C. H. (1958), ‘Infrared and optical masers’, Physical Review, 112 (6), 1940–9.
  24. Scheller, M., Yarborough, J. M., Moloney, J. V., et al. (2010), ‘Room temperature continuous wave miliwatt terahertz source’, Optics Express, 18 (26), 27112–7.
  25. Van der Ziel, J. P. (1979), ‘Spectral broadening of pulsating AlxGa1-xAs double heterostructure lasers’, IEEE Journal of Quantum Electronics, 15 (11), 1277–81.
  26. Wilmsen, C., Temkin, H., a Coldren, L. A. (1999), Vertical-Cavity Surface-Emitting Lasers – Design, Fabrication, Characterization and Applications (Cambridge: Cambridge University Press).
  27. Yariv, A. (1989), Quantum Electronics, 3ydd argraffiad (New York: Wiley).
  28. Yu, S. F. (2003), Analysis and Design of Vertical Cavity Surface Emitting Lasers (New Jersey: Wiley).
  29. Zhao, B., Chen, T. R., a Yariv, A. (1993), ‘A comparison of amplitude-phase coupling and linewidth enhancement in semiconductor QW and bulk lasers’, IEEE Journal of Quantum Electronics, 29 (4), 1027–30.