CC BY
2Broadband radiation detector based on laser-induced graphene
embedded in polyimide
A. Telegin1*, Yu. Sukhorukov, R.G. Zonov2, K. Mikheev2, G. Mikheev2
1-M.N. Mikheev Institute of Metal Physics, UB of RAS, 620108, Yekaterinburg, Russia 2- Udmurt Federal Research Center, UB of RAS, 426067, Izhevsk, Russia
* telegin@imp.uran.ru
The unique physicochemical properties of graphene offer broad possibilities for its use across all technical sectors. For instance, the zero bandgap in graphene's energy spectrum suggests it for creating an electromagnetic radiation detector working from ultraviolet to the submillimeter range. However, graphene has low light absorption and, consequently, low optical efficiency. In study [1], a high-speed and cost-effective method of synthesis of graphene through the pyrolysis of a polyimide film subjected to laser treatment by continuous CO2 laser was considered. The formation of a porous graphene structure (LIG) significantly increased light absorption and led to reveal ultrafast photoinduced effects in visible range [1]. However, the spectral and low-frequency characteristics of the LIG are less studied.
In this work, the bolometric characteristics of the newly synthesized LIG samples (Fig.1a,b) are studied under exposure to visible and infrared light. It is shown that the thermal resistance coefficient of LIG is P~0.05%/deg at ambient conditions and increases to ~0.15%/deg upon cooling. The sensitivity of the LIG detector at a wavelength of 532 nm is ~0.08%/W at frequencies up to 10 kHz (Fig.lc), which is an only order of magnitude lower than the literature data for the best graphene structures. The spectral dependences of the AY are measured up to 21 ^m due to technical limitations of the setup.
Fig.1 a) Images of a fragment of the LIG sample, b) the LIG detector on a polyimide substrate, c) Frequency dependence of the photoresponse AY of the LIG (1) and the ideal bolometer (2).
The frequency dependence of the LIG is formed by the contribution of several processes [2]. The first, thermal (bolometric), is associated with the heating of LIG due to the light absorption. The second is weakly dependent on the frequency of the emitter and is related to the photoinduced change in mobility and concentration of charge carriers due to trapping at defects. The spectral behavior is well described by Wien's law, except for features related to the generation of photoelectrons in the varieties of 2D graphene layers of porous graphene and light absorption in the optical scheme.
Therefore, the simple synthesis technology and wide spectral, time and frequency ranges of LIG can be considered for creating broadband bolometric type electromagnetic radiation detectors.
This work was performed within the framework of the state assignment of the Ministry of Education and Science of the Russian Federation (SPIN № 122021000036-3 and 1021032422167-7-1.3.2).
[1] K.G. Mikheev, et al, Laser-induced graphene on a polyimide film: observation of the photon drag effect, Technical Physics Letters, vol.46, pp. 458-461, (2020).
[2] Yu.P. Sukhorukov, et al, Laser-induced graphene based visible and near-infrared radiation detector, Optical materials, vol.133, p. 112957, (2022).
