Ultra Sensitive Bio-Detection Using Whispering Gallery Spheres and Intra-Cavity Polarization Mode Beating (PMB)

50-200微米量级的球（或腔）如果Q值很高，则必须满足非常尖锐的共振条件。如果一个生物实体通过si - o抗原复合物附着在球体上，那么，当抗原附着时，低语廊模式看到的有效折射率会有一个小的变化。这一构想已被用于灵敏的生物检测。通过在激光腔内放置这样的装置，可以测量的不是与生物实体附着相关的波长位移，而是模式跳动位移。通过将光域（波长移位）的测量转换为RF（射频）域的测量，即模式跳动的移位，测量的灵敏度可以提高几个数量级。该奖项由电气和通信系统司和国际科学与工程办公室联合支持。

0423873MorseA Whispering Gallery sphere of the order of 50-200 microns must satisfy a very sharp resonance condition if the Q of the sphere (or cavity) is high. If a biological entity is attached to the sphere through an Si-O-antigen complex, then, when an antigen attaches, there will be a small shift in the effective refractive index that the Whispering Gallery mode(s) sees. This conceit has been used for sensitive biodetection. By placing such a device within a laser cavity, it is possible to measure not a wavelength shift associated with the attachment of the biological entity, but a mode beating shift. By converting a measurement in the optical domain (wavelength shift) to a measurement in the RF (Radio Frequency) domain, i.e., a shift in the mode beating, sensitivity of measurement can be increased by several orders of magnitude.This award is jointly supported by the Division of Electrical and Communications Systems and the Office of International Science and Engineering.