Unlocking new physics in controllably strained two dimensional materials
"We will use strain engineering as an enabling tool to study previously inaccessible or hard-to-study phenomena in two-dimensional atomic crystals (2DACs: graphene, bilayer graphene, and monolayer transition metal dichalcogenides)...
"We will use strain engineering as an enabling tool to study previously inaccessible or hard-to-study phenomena in two-dimensional atomic crystals (2DACs: graphene, bilayer graphene, and monolayer transition metal dichalcogenides). In our first objective, we develop unique experimental tools to control and characterize mechanical strain in 2DACs. These are the distinguishing features of our approach: (i) The use of very low disorder suspended devices; (ii) Both uniform and controlled non-uniform strain will be induced; (iii) The level of strain will be precisely adjusted and determined in-situ during measurements. We will then use controllably-strained samples to study electrical, mechanical, thermal, and optical properties of 2DACs:
Application of strain in suspended graphene will be shown to control amplitudes and dispersion relation of flexural out-of-plane phonons (FPs), a mode unique to 2D and quasi-2D materials. We will demonstrate, for the first time, that FPs dominate electrical, thermal, and mechanical of suspended graphene. Moreover, we will show dramatic mechanical softening of graphene in the regime of weak strain, similar to ""entropic spring"" behaviour seen in polymers.
We will engineer strain distributions in high-mobility suspended graphene devices that translate into near-constant ""pseudomagnetic field"" and observe Quantum Hall-like quantization at zero external magnetic field.
Strain-induced changes in topology of the band structure of bilayer graphene will be shown to affect Quantum Hall states and the Berry phase.
Through strain engineering, we will controllably adjust - and even make spatially dependent - the band gap energy and binding energies of excitons in monolayer transition metal dichalcogenides (TMDCs). We will study complex interplay between and direct and indirect excitons and look for emergence of a new phase of matter, an excitonic insulator, in strained narrow-bandgap TMDC.
"ver más
Seleccionando "Aceptar todas las cookies" acepta el uso de cookies para ayudarnos a brindarle una mejor experiencia de usuario y para analizar el uso del sitio web. Al hacer clic en "Ajustar tus preferencias" puede elegir qué cookies permitir. Solo las cookies esenciales son necesarias para el correcto funcionamiento de nuestro sitio web y no se pueden rechazar.
Cookie settings
Nuestro sitio web almacena cuatro tipos de cookies. En cualquier momento puede elegir qué cookies acepta y cuáles rechaza. Puede obtener más información sobre qué son las cookies y qué tipos de cookies almacenamos en nuestra Política de cookies.
Son necesarias por razones técnicas. Sin ellas, este sitio web podría no funcionar correctamente.
Son necesarias para una funcionalidad específica en el sitio web. Sin ellos, algunas características pueden estar deshabilitadas.
Nos permite analizar el uso del sitio web y mejorar la experiencia del visitante.
Nos permite personalizar su experiencia y enviarle contenido y ofertas relevantes, en este sitio web y en otros sitios web.