Temperature sensor based on high-Q polymethylmethacrylate optical microbubble

Abstract

A new flexible method to fabricate a temperature sensor based on polymethylmethacrylate (PMMA) optical microbubbles, using a volume-controllable pipette, is demonstrated. The high quality factor of the cavity is guaranteed by the smooth wall of the microbubble. The shape and refractive index of the microbubbles change with the surrounding temperature, which leads to the obvious displacement of the whispering gallery mode transmission spectrum. As the surrounding temperature increases, the spectrum undergoes a significant blue shift, hence the microresonator can be used for temperature sensing. A sensitivity of 39 pm °C−1 is obtained in a PMMA microbubble with a diameter of 740 µm. This work suggests a new convenient approach to achieving high-quality flexible microscale sensors.

Whispering Gallery Mode Optical Microresonators: Structures and Sensing Applications

“…Based on the aforementioned foundations, in recent years, He et al. proposed a microbubble resonator based on PMMA volume controllable with a temperature sensitivity of 39 pm °C −1 …”

“…With the continuous improvement of WGMRs in optical sensing, many novel geometric structures have appeared in recent years, such as: microdisk, microbubble, microbottle, microtube, microcylinder, etc. These new resonators are widely used in the field of physical biochemistry.…”

Sensing and lasing applications of whispering gallery mode microresonators

“…The fabrication method of microbottles and microbubbles are similar and more flexible than the first two kinds of geometries 25,38,39 . A simple process of fabricating a microbottle is to taper the optical fiber two times in two adjacent places.…”

“…In the early studies, microbubbles were updated from heating microcapillaries with a gas pressure. Recently, some novel methods are applied to fabricate microbubbles [38][39][40] . For instance, Wang et al prepared microbubbles based on the drying process of the colloidal quantum dots (CQDs)/ polymethyl methacrylate (PMMA) nanocomposite droplets 25 .…”

Highly Sensitive Temperature Sensor Based on Hollow Microsphere for Ocean Application

“…Microbubble sensors are also used for temperature measurement. He et al [23] used polymethylmethacrylate to fabricate microbubble, but the sensitivity of 39 pm/°C is relatively low. Ward et al [24] heated silica glass capillary with CO 2 laser to form microbubble.…”