<p>Graphene-based infrared detectors exhibit remarkable thermoelectric and photoresponse properties, yet their stability under varying environmental conditions remains a critical challenge. This study investigates the temperature-dependent performance of a graphene/hBN/(gold-hBN-gold) heterostructure infrared detector, focusing on the Seebeck coefficient, voltage response, and thermal stability. By analyzing the system under applied voltages of 0.3 to 0.6 V and temperatures from 300 to 500 K, we noted an enhanced Seebeck coefficient, achieving values up to <InlineEquation ID="IEq1"> <InlineMediaObject> <ImageObject Color="BlackWhite" FileRef="11082_2025_8453_Article_IEq1.gif" Format="GIF" Height="19" Rendition="HTML" Resolution="72" Type="Linedraw" Width="89" /> </InlineMediaObject> <EquationSource Format="TEX">\(-140\,\upmu\,{\rm V/ K}\)</EquationSource> </InlineEquation>. The thermoelectric figure of merit (ZT) improves with temperature, though its magnitude is inversely proportional to the initial operating temperature, highlighting the role of hBN in suppressing phonon-mediated thermal losses. Furthermore, the Brody parameter <InlineEquation ID="IEq2"> <InlineMediaObject> <ImageObject Color="BlackWhite" FileRef="11082_2025_8453_Article_IEq2.gif" Format="GIF" Height="19" Rendition="HTML" Resolution="72" Type="Linedraw" Width="116" /> </InlineMediaObject> <EquationSource Format="TEX">\((\beta = 0.58-0.7)\)</EquationSource> </InlineEquation> confirms spectral selectivity in the <InlineEquation ID="IEq3"> <InlineMediaObject> <ImageObject Color="BlackWhite" FileRef="11082_2025_8453_Article_IEq3.gif" Format="GIF" Height="14" Rendition="HTML" Resolution="72" Type="Linedraw" Width="54" /> </InlineMediaObject> <EquationSource Format="TEX">\(36-54\;\)</EquationSource> </InlineEquation> THz range. Current-density analysis reveals asymmetric transport behavior, with quantum tunneling dominating at positive biases <InlineEquation ID="IEq4"> <InlineMediaObject> <ImageObject Color="BlackWhite" FileRef="11082_2025_8453_Article_IEq4.gif" Format="GIF" Height="19" Rendition="HTML" Resolution="72" Type="Linedraw" Width="43" /> </InlineMediaObject> <EquationSource Format="TEX">\((> 2\,)\)</EquationSource> </InlineEquation> V and stable p-n junction dynamics at negative biases. These findings demonstrate that optimized doping, hBN integration, and voltage control can mitigate thermal stress, enhancing graphene detectors’ scalability for infrared applications.</p>

Advancing infrared detection: graphene’s potential and stability in varied environments

期刊论文
发表日期：

2025年9月24日

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Elahe Javanshoor,
Sohrab Behnia,
Fatemeh Nemati

摘要

Graphene-based infrared detectors exhibit remarkable thermoelectric and photoresponse properties, yet their stability under varying environmental conditions remains a critical challenge. This study investigates the temperature-dependent performance of a graphene/hBN/(gold-hBN-gold) heterostructure infrared detector, focusing on the Seebeck coefficient, voltage response, and thermal stability. By analyzing the system under applied voltages of 0.3 to 0.6 V and temperatures from 300 to 500 K, we noted an enhanced Seebeck coefficient, achieving values up to \(-140\,\upmu\,{\rm V/ K}\) . The thermoelectric figure of merit (ZT) improves with temperature, though its magnitude is inversely proportional to the initial operating temperature, highlighting the role of hBN in suppressing phonon-mediated thermal losses. Furthermore, the Brody parameter \((\beta = 0.58-0.7)\) confirms spectral selectivity in the \(36-54\;\) THz range. Current-density analysis reveals asymmetric transport behavior, with quantum tunneling dominating at positive biases \((> 2\,)\) V and stable p-n junction dynamics at negative biases. These findings demonstrate that optimized doping, hBN integration, and voltage control can mitigate thermal stress, enhancing graphene detectors’ scalability for infrared applications.