Frequency shift of the spectrum of an incident optical pulse by an intense THz pulse inducing cross-phase modulation (XPM) in a nonlinear dielectric slab is analyzed. The effect is predicted with a high degree of accuracy using the well-known transmission line matrix (TLM) technique. In this research, to model the THzinduced temporal and spatial variation of the dielectric permittivity of the nonlinear dielectric slab, the transmission lines of the TLM method are loaded with open shunt stubs. The parameters of the stubs are modified in accordance with the refractive index variation of the dielectric slab, here ZnTe, induced by the strong THz pulse. The obtained numerical results are verified with a recently reported experimental work.
2. Alfano, R. R., Q. X. Li, T. Jimbo, J. T. Manassah, and P. P. Ho, "Induced spectral broadening of a weak picosecond pulse in glass produced by an intense picosecond pulse," Opt. Lett., Vol. 11, 626-628, 1986.
3. Schadt, D. and B. Jaskorzynska, "Generation of short pulses from CW light by influence of crossphase modulation (CPM) in optical fibers," Electron. Lett., Vol. 23, 1090-1091, 1987.
4. Agrawal, G. P., "Modulation instability induced by cross-phase modulation," Phys. Rev. Lett., Vol. 59, 880-883, 1987.
5. Monerie, M. and Y. Durteste, "Direct interferometric measurement of nonlinear refractive index of optical fiber by cross-phase modulation," Electron. Lett., Vol. 23, 961-963, 1987.
6. Alfano, R. R. and P. P. Ho, "Self-, cross-, and induced-phase modulations of ultrashort laser pulse propagation," IEEE J. Quantum Electron., Vol. 24, 351-364, 1988.
7. Shtaif, M., "An analytical description of cross-phase modulation in dispersive optical fibers," Opt. Lett., Vol. 23, 1191-1193, 1998.
8. Lee, J. H. and I. Jacobs, "Cross-phase modulation analysis using sinusoidally modulated signal," Proc. SPIE, Vol. 4087, 298-307, 2000.
9. Henesian, M. A., S. N. Dixit, C. J. Chen, P. K. A. Wai, and C. R. Menyuk, "Simulations of spectral broadening by crossphase modulation (XPM) with chaotic light pulses," Proc. SPIE, Vol. 1870, 2-13, 1993.
10. Islam, M. N., L. F. Mollenauer, and R. H. Stolen, "Cross-phase modulation in optical fibers," Opt. Lett., Vol. 12, 625-627, 1987.
11. Baldeck, P. L. and R. R. Alfano, "Induced-frequency shift of copropagating ultrafast optical pulses," Appl. Phys. Lett., Vol. 52, 1939-1941, 1988.
12. Wilhelmi, B., M. Kaschke, and W. Rudolph, Ultrafast wavelength shift of light induced by light, Proc. SPIE, Vol. 1319, 81-82, 1990.
13. Shen, Y., T. Watanabe, D. A. Arena, C. C. Kao, J. B. Murphy, T. Y. Tsang, X. J. Wang, and G. L. Carr, "Nonlinear cross-phase modulation with intense single-cycle terahertz pulses," Phys. Rev. Lett., Vol. 99, 043901-043904, 2007.
14. Yariv, A. and P. Yeh, Photonics: Optical Electronics in Modern Ommunications, Oxford University Press, USA, 2006.
15. Cai, Y., I. Brener, J. Lopata, J. Wynn, L. Pfeiffer, J. B. Stark, Q. Wu, X. C. Zhang, and J. F. Federici, "Coherent terahertz radiation detection: Direct comparison between free-space electro-optic sampling and antenna detection," Appl. Phys. Lett., Vol. 73, 444-446, 1998.
16. Hoefer, W. J. R., "The transmission-line matrix method theory and applications," IEEE Trans. Microw. Theory Tech., Vol. 33, 882-893, 1985.
17. Johns, P. B. and R. L. Beurle, "Numerical solution of 2-dimensional scattering problems using a transmission-line matrix," Proc. Inst. Elec. Eng., Vol. 118, 1203-1208, 1971.