Monolayer Thermoelectric Transport Reveals 2D Dirac Oscillator Effects for Energy Harvesting Advances

Graphene continues to fascinate physicists and materials scientists due to its remarkable properties, and a comprehensive understanding of how it conducts both electricity and heat is now vital for creating advanced technologies. Juan A. Cañas, Daniel A. Bonilla, and A. Martín-Ruiz, from the Instituto de Ciencias Nucleares at the Universidad Nacional Autónoma de México, present research that explores how localized strain, or stretching and compressing of the material, affects its thermoelectric behaviour, which governs its ability to convert temperature differences into electrical energy. The team models these strains as disturbances that influence the way electrons move within graphene, using a novel approach based on the behaviour of particles in quantum mechanics. This work demonstrates how mechanical stress alters key properties like electrical conductivity and the Seebeck coefficient, offering a theoretical basis for designing graphene-based devices that efficiently harvest energy or control heat flow through precise strain engineering.

Strain Engineering for Enhanced Graphene Thermoelectricity

Graphene, a remarkable material in condensed matter physics, possesses exceptional electronic, mechanical, and thermal properties. Understanding its thermoelectric behaviour is crucial for developing innovative nanodevices and energy harvesting technologies. Thermoelectric materials directly convert heat into electrical energy, offering potential solutions for recovering wasted heat and creating solid-state refrigeration systems. Recent investigations demonstrate that applying strain fields to graphene can significantly modify its electronic band structure and, consequently, its thermoelectric properties.

Strain alters the distances and angles between carbon atoms, inducing changes in the density of states and carrier mobility. These modifications offer a pathway to engineer graphene’s thermoelectric performance, potentially overcoming its intrinsic limitations. This work investigates the influence of strain fields on thermoelectric transport in graphene, modelling the system using a theoretical approach that captures the unique electronic characteristics of this two-dimensional material. The primary objective of this research is to elucidate the relationship between strain magnitude, strain configuration, and the resulting thermoelectric coefficients, specifically the Seebeck coefficient, electrical conductivity, and thermal conductivity.

Graphene’s Electronic and Thermal Transport Properties

This extensive list comprises references related to graphene, its properties, and related materials and concepts. The references highlight several key themes, including the fundamental properties of graphene, its exceptional thermal conductivity, and electron transport. The list also includes references on the mechanical properties of graphene and structures like nanobubbles. Several papers focus on graphene nanoribbons and quantum dots, which exhibit modified electronic properties due to edge effects and quantum confinement. References also explore theoretical and computational methods used to model graphene, including tight-binding calculations.

Finally, a cluster of papers investigate graphene’s potential for thermoelectric applications, converting heat to electricity. Key themes emerge from this collection of references. Quantum confinement effects in graphene nanoribbons and quantum dots are heavily investigated. Theoretical and computational modelling plays a strong role in understanding and predicting graphene’s behaviour. The bibliography points to potential applications in thermoelectrics and electronics.

Strain Tuning Thermoelectric Transport in Graphene

This study investigates the thermoelectric transport properties of graphene with randomly distributed strain fields, modelling these as localized disturbances using a theoretical approach. The research develops a theoretical framework linking strain-induced modifications to an effective field, which then informs a kinetic theory to compute thermoelectric transport coefficients. Through this approach, the team derived analytical expressions for electrical conductivity, the Seebeck coefficient, and thermal conductivity, revealing how these properties are influenced by the size, density, and strength of the effective field. The results demonstrate that conductivity and thermal conductivity can be tuned by these strain-related parameters, with pronounced dips observed in relaxation time and conductivity spectra due to quasi-bound states and resonant scattering. Importantly, the analysis highlights the limitations of simpler approximation methods and underscores the necessity of a more complete treatment to accurately capture these effects. Future work could explore the impact of different strain configurations and investigate the potential for optimizing thermoelectric performance through targeted strain engineering in graphene-based devices.