Commercial polycarbonate track-etched membranes as substrates for low-cost optical sensors

Abstract

Porous materials have become one of the best options for the development of optical sensors, since they maximize the interaction between the optical field and the target substances, which boosts the sensitivity. In this work, we propose the use of a readily available mesoporous material for the development of such sensors: commercial polycarbonate track-etched membranes. In order to demonstrate their utility for this purpose, we firstly characterized their optical response in the near-infrared range. This response is an interference fringe pattern, characteristic of a Fabry–Pérot interferometer, which is an optical device typically used for sensing purposes. Afterwards, several refractive index sensing experiments were performed by placing different concentrations of ethanol solution on the polycarbonate track-etched membranes. As a result, a sensitivity value of around 56 nm/RIU was obtained and the reusability of the substrate was demonstrated. These results pave the way for the development of optical porous sensors with such easily available mesoporous material.

Heat current rectification in segmented XXZ chains

“…Investigations of rectifiers have been done also at the quantum level using other energy carriers such as photons [10], electrons [11][12][13] and spins [14][15][16][17][18][19][20][21]. In [17,18], asymmetric quantum structures and hybrid material junctions are identified as the main ingredients for thermal rectification.…”

Three-terminal normal-superconductor junction as thermal transistor

“…Thermal management at nanoscale is receiving significant research attention [1], and there have been a variety of topics on this subject: spin caloritronics [2], near-field radiative heat transfer [3,4], energy harvesting [5], cooling [6][7][8][9], thermometry [10][11][12], heat-assisted magnetic recording [13], and so on. As the diodes and transistors are the basic elements of electronic circuits, various thermal diodes [1,[14][15][16][17][18][19][20][21][22] and thermal transistors [23][24][25][26][27][28][29][30][31][32][33][34][35] have been proposed in order to realize the solid-state thermal circuits. In a thermal diode, heat current changes the magnitude with the reversal of the temperature bias.…”

“…Recently, superconductors, especially Josephson junctions have been applied to construct various thermal devices, such as thermal diode [18,19], heat interferometer [41], heat modulator [42], thermoelectric device [43], thermal router [44], thermal memory [45], and the above mentioned thermal transistor in Josephson junction [31]. In this work, we investigate heat amplification using a three-terminal normalsuperconductor (NS) junction [see Figure 1(b)], by utilizing the possible NDTC effect in a two-terminal NS junction [46,47].…”

Thermal rectification in a double quantum dots system with a polaron effect

“…In analogy to electric diodes as the primary building block in the electronics industry, thermal diode or rectifier becomes crucial in managing heat flow by changing heat current magnitude with the reversal of temperature bias. Thermal rectification has been reported in various systems such as magnonic junction 4 , spin Seebeck engine 5,6 , topological insulator-superconductor junction 7 , normal metalsuperconductor junction [8][9][10] , near field raditative heat transfer 13 , geometric asymmetric structures [14][15][16][17] , etc.. Heat current can be transferred via different types of energy carriers 18,19 , such as magnons 4-6 , electrons [7][8][9][10][11][12] , photons 13,20 , phonons 21 , acoustic wave 22,23 , and etc.. Regardless of the type of the junctions and energy carriers, the key ingredient required for achieving thermal rectification is structural asymmetry 24 .…”