Wide Bandgap Photonic Structures
CuCl is an ionic, wide bandgap semiconductor. Because its lattice constants closely match those of silicon thus CuCl and Si create very promising material system. The optical properties of copper chloride are also very interesting. The bandgap energy is of 3.4 eV at room temperature which is comparable to bandgaps of GaN or ZnO for instance. CuCl has been widely researched for many years because of another interesting property very high exciton binding energy of 190 meV. This value is much higher than for competing materials and much above room temperature thermal energy. It makes CuCl potential candidate material for highly efficient UV/blue lasers, low threshold polariton lasers etc. working stable at room temperature and above. Before attempt of building such devices materials has to be thoroughly characterised first. Our attention is focused on optical properties of copper chloride.
References:1. Dominik Danieluk, A. L. Bradley, A. Mitra, L. O'Reilly, O. F. Lucas, A. Cowley, P. J. McNally, B. Foy, E. McGlynn, "Optical properties of undoped and oxygen doped CuCl films on silicon substrates", Journal of Materials Science: Materials in Electronics, DOI 10.1007/s10854-007-9448-5
2.A. Mitra, L. O'Reilly, O. F. Lucas, Gomathi Natarajan, D. Danieluk, A. L. Bradley, P. J. McNally, S. Daniels, D. C. Cameron, A. Reader, and M. Martinez-Rosas, "Optical properties of CuCl films on silicon substrates", phys. stat. sol. (b), 1 7 (2008), DOI 10.1002/pssb.200844021
3.Dominik Danieluk, A.L. Bradley, A. Mitra, P.J. McNally, L. O'Reilly, G. Natarajan, A. Cowley, B. Foy, E.McGlynn and D.C. Cameron "Optical properties of CuCl on silicon substrate towards UV photonic devices" Oral presentation at: Second International Conference on Optical, Optoelectronic and Photonic Materials and Applications 2007, London 30 July – 3 August 2007
4. F. O. Lucas, P.J. McNally, A. Cowey, L. Bradley, D. Danieluk "Structural, Optical and Electrical Properties of Co-evaporated CuCl/KCl films" Oral presentation at: Third International Conference on Optical, Optoelectronic and Photonic Materials and Applications, Edmonton, 20-25 July 2008
5. D. Danieluk, A.L. Bradley, P.J. McNally, L. O'Reilly, O. F. Lucas, G. Natarajan, S. Daniels, E.McGlynn, A. Cowley, B. Foy and D.C. Cameron "Optical properties of CuCl on Si substrates – toward UV photonic devices" Poster at: Photonics Ireland 2007, Galway, 24-26 September 2007
6. D.Danieluk, A.L. Bradley, E. Degirmenci, P.Landais "CuCl photonic crystal THz waveguide" Oral presentation at: Semiconductor and Integrated Optoelectronics Conference, Cardiff , 6-8 April 2009