We show how an electromagnetic cavity with arbitrarily high <i>Q</i> and small (bounded) modal volume can be formed in two or three dimensions with a proper choice of dielectric constants. Unlike in previous work, neither a complete photonic bandgap nor a trade-off in mode localization for <i>Q</i> is required. Rather, scattering and radiation are prohibited by a perfect mode match of the TE-polarized modes in each subsection of a Bragg resonator. <i>Q</i> values in excess of 10<sup>5</sup> are demonstrated through finite-difference time-domain simulations of two- and three-dimensional structures with modal areas or volumes of the order of the wavelength squared or cubed.
© 2002 Optical Society of America
M. R. Watts, S. G. Johnson, H. A. Haus, and J. D. Joannopoulos, "Electromagnetic cavity with arbitrary Q and small modal volume without a complete photonic bandgap," Opt. Lett. 27, 1785-1787 (2002)