Whispering gallery mode (WGM) resonance was created in a spherical micro drop. A gradual shift in the resonance were observed. For a 600 nm droplet radius, the blue shift were 1.5, 0.7, 3.7 nm. It was estimated that such a shift corresponds to a reduction in optical radius of the droplet by 1.3, 0.6, 3.3 nm respectively. The droplet was created from a solution of glycerol, methanol and rhodamine 6G dye, and was trapped and levitated in a modified Paul trap. The WGMs were created by optically exciting the dye material from an external 532 nm cw laser beam. A shift in the WGM was observed during a gradual increase in power of the excitation laser, and a reason for such a shift was thought to be thermal evaporation of the liquid. For a larger droplet an initial 0.1 nm thermal expansion was also estimated, preceding the volume contraction. Such an expansion was negligible for a smaller droplet. The rate of change of the blue shift depends upon initial radius of the droplet. For the smaller droplet the estimated rate of change of WGM with a change in optical radius, was 0.771. For larger droplet, this rate is lower.

回音壁模式 (WGM) 共振是在球形微滴中产生的。观察到共振的逐渐变化。对于 600 nm 的液滴半径，蓝移分别为 1.5、0.7、3.7 nm。据估计，这种偏移对应于液滴光学半径分别减少1.3、0.6、3.3 nm。该液滴由甘油、甲醇和罗丹明 6G 染料的溶液制成，并被捕获并悬浮在改良的保罗陷阱中。 WGM 是通过外部 532 nm 连续激光束光学激发染料材料而产生的。在激发激光功率逐渐增加的过程中观察到 WGM 的变化，并且这种变化的原因被认为是液体的热蒸发。对于较大的液滴，在体积收缩之前还估计了初始 0.1 nm 的热膨胀。对于较小的液滴来说，这种膨胀可以忽略不计。蓝移的变化率取决于液滴的初始半径。对于较小的液滴，WGM 随光学半径变化的估计变化率为 0.771。对于较大的液滴，该速率较低。