AVS 63rd International Symposium & Exhibition
    Electronic Materials and Photonics Thursday Sessions
       Session EM-ThP

Paper EM-ThP5
A bi-functional Bolometer with Sensitivity to IR Radiation and Hot Air Induced Temperature Variation

Thursday, November 10, 2016, 6:00 pm, Room Hall D

Session: EMPD Poster Session
Presenter: Evgenia Vaganova, The Hebrew University of Jerusalem, Israel
Correspondent: Click to Email

ABSTRACT We have shown previously that doping a poly(4-vinyl pyridine)/pyridine gel with an ester group-containing polymer (e.g. poly(butyl methacrylate)) (polymer acids as additives) expands the wavelength range of the gel photoelectrical sensitivity from the uv into the infra-red. Here we characterize the temporal response of the gel resistivity and demonstrate its ability to operate as a bi-functional bolometer. At constant room temperature, the bolometer can function as a rapidly responding IR detector. It can also respond to temperature variation produced by hot air, but with a much longer time constant. Measurements are shown in the figure below.

  1. b)

    Figure. a) Time dependence of the resistance changes of the polymer gel due to IR irradiation at 1 μm. The down pointing arrows indicate switch-on of the radiation source while the up pointing arrows indicate switch-off. b) Time dependence of the resistance changes of the polymer gel in response to temperature variation produced by hot air. The maximum temperature change was 4̊C (26̊C - 30̊C).

    The fractional change in resistance caused by IR irradiation at 1mm is ΔR/R0 = 0.13; the fractional change caused by hot air induced temperature variation - ΔR/R0 = 0.06/1°C. The relaxation rate of the IR response following switch-off is 260%/s. The temperature-induced relaxation curve could be fit to an exponential function with two time constants – t1=0.148s and t2=17.11s. Analysis of the relaxation of the photo-response was limited by the time resolution of the resistance measurements, i.e. 0.02s.

    Polymer/liquid pyridine interactions2 are considered to be responsible for this interesting functionality of the polymer blend and they will be discussed.

    References:

  1. E. Vaganova, E. Wachtel, A. Goldberg, S.Yitzchaik, J. Phys. Chem. C, 2012, 116, 2508.

  2. B. Sedlacek, J. Spevachek et al. Macromolecules, 1984, 17, 825.