Changing character of electronic transitions in graphene: From single-particle excitations to plasmons

Znanstveni rad - Izvorni znanstveni rad

• Autor: Dino Novko
• Autor: Vito Despoja
• Autor: Marijan Šunjić
• Autorova ustanova: Sveučilište u Zagrebu; Prirodoslovno-matematički fakultet; (Fizički odsjek)
• Znanstveno / umjetničko područje, polje i grana: PRIRODNE ZNANOSTI; Fizika

Sažetak (engleski)

In this paper we clarify the nature of π and π + σ electron excitations in pristine graphene. We clearly demonstrate the continuous transition from single particle to collective character of such excitations and how screening modifies their dispersion relations. We prove that π and π + σ plasmons do exist in graphene, though occurring only for a particular range of wave vectors and with finite damping rate. Particular attention is paid to comparing the theoretical results with available EELS measurements in optical (Q ≈ 0) and other (Q not equal 0) limits. The conclusions, based on microscopic numerical results, are confirmed in an approximate analytical approach.

• Ključne riječi (engleski): Pi plasmon; graphene; EELS
• Jezik: engleski
• Vrsta publikacije: Znanstveni rad - Izvorni znanstveni rad
• Status objave: Objavljen
• Vrsta recenzije: Recenziran - međunarodna recenzija
• Verzija publikacije: Objavljena verzija rada (izdavačev PDF)
• Naslov časopisa: Physical review B: Condensed matter and materials physics
• Brojčani podaci: vol. 91, br. 19, 195407
• p-ISSN: 1098-0121
• e-ISSN: 1550-235X
• DOI: https://doi.org/10.1103/PhysRevB.91.195407
• URN:NBN: urn:nbn:hr:217:007139
• Datum objave publikacije: 2015
• URL dokumenta: http://link.aps.org/doi/10.1103/PhysRevB.91.195407
• Vrsta resursa: Tekst
• Prava pristupa: Otvoreni pristup
• Javna napomena: Copyright (2015) by the American Physical Society. Received 15 April 2015; revised manuscript received 25 April 2015; published 11 May 2015.
• Datum i vrijeme pohrane: 2020-01-11 19:06:58