Open AccessMicro displacement sensor based on line-defect resonant cavity in photonic crystal
Author(s) -
Zhiyuan Xu,
Liangcai Cao,
ChengBo Gu,
Qingsheng He,
Guofan Jin
Publication year - 2006
Publication title -
optics express
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/opex.14.000298
Subject(s) - optics , finite difference time domain method , displacement (psychology) , materials science , photonic crystal , q factor , sensitivity (control systems) , optoelectronics , physics , resonator , electronic engineering , psychology , psychotherapist , engineering
A micro displacement sensor and its sensing technique based on line-defect resonant cavity in photonic crystals (PhCs) are presented. The line-defect resonant cavity is formed by a fixed and a mobile PhC segments. With a proper operating frequency, a quasi-linear measurement of micro-displacement is achieved with sensitivity of 1.15 a(-1) ( a is the lattice constant) and Q factor of 40. The sensitivity can be adjusted easily by varying either Q factor or operating frequency of the sensing system. In addition, the sensing range can be broadened to -0.55 a ~0.60 a by using multiple operating frequencies. The properties of the micro displacement sensor are analyzed theoretically and simulated using finite-difference time-domain (FDTD) method.