Nonadiabatic phonons within the doped graphene layers of XC6 compounds

被引：47

作者：

Dean, Mark P. M. ^{[1
]}

Howard, Christopher A. ^{[2
,3
]}

Saxena, Siddharth S. ^{[1
]}

Ellerby, Mark ^{[2
,3
]}

机构：

[1] Univ Cambridge, Cavendish Lab, Cambridge CB3 0HE, England

[2] UCL, London Ctr Nanotechnol, London WC1E 6BT, England

[3] UCL, Dept Phys & Astron, London WC1E 6BT, England

来源：

PHYSICAL REVIEW B | 2010年 / 81卷 / 04期

基金：

英国工程与自然科学研究理事会;

关键词：

BORN-OPPENHEIMER APPROXIMATION; RAMAN-SCATTERING; INTERCALATION COMPOUNDS; CARBON NANOTUBES; GRAPHITE; SUPERCONDUCTIVITY; RENORMALIZATION; SPECTROSCOPY; BREAKDOWN; DISORDER;

D O I：

10.1103/PhysRevB.81.045405

中图分类号：

T [工业技术];

学科分类号：

08 ;

摘要：

We report Raman-scattering measurements of BaC6, SrC6, YbC6, and CaC6, which permit a systematic study of the phonons and the electron-phonon interaction within the doped graphene layers of these compounds. The out-of-plane carbon phonon softens as the spacing of the graphene layers is reduced in the series BaC6, SrC6, YbC6, and CaC6. This is due to increasing charge in the pi* electronic band. Electron-phonon interaction effects between the in-plane carbon modes at approximate to 1500 cm(-1) and the pi* electrons cause a strong nonadiabatic renormalization. As charge is transferred into the pi* band, these nonadiabatic effects are found to increase concurrent with a reduction in the phonon lifetime.

引用

页数：5

共 38 条

[1] Phonons and related crystal properties from density-functional perturbation theory [J].

Baroni, S ;

de Gironcoli, S ;

Dal Corso, A ;

Giannozzi, P .

REVIEWS OF MODERN PHYSICS, 2001, 73 (02) :515-562

[2] Electron-phonon interaction in graphite intercalation compounds [J].

Boeri, Lilia ;

Bachelet, Giovanni B. ;

Giantomassi, Matteo ;

Andersen, Ole K. .

PHYSICAL REVIEW B, 2007, 76 (06)

[3] Direct Observation of Born-Oppenheimer Approximation Breakdown in Carbon Nanotubes [J].

Bushmaker, Adam W. ;

Deshpande, Vikram V. ;

Hsieh, Scott ;

Bockrath, Marc W. ;

Cronin, Stephen B. .

NANO LETTERS, 2009, 9 (02) :607-611

[4] Theoretical explanation of superconductivity in C6Ca -: art. no. 237002 [J].

Calandra, M ;

Mauri, F .

PHYSICAL REVIEW LETTERS, 2005, 95 (23)

[5] Possibility of superconductivity in graphite intercalated with alkaline earths investigated with density functional theory [J].

Calandra, Matteo ;

Mauri, Francesco .

PHYSICAL REVIEW B, 2006, 74 (09)

[6]

CALANDRA MJ, COMMUNICATION

[7] Monitoring dopants by Raman scattering in an electrochemically top-gated graphene transistor [J].

Das, A. ;

Pisana, S. ;

Chakraborty, B. ;

Piscanec, S. ;

Saha, S. K. ;

Waghmare, U. V. ;

Novoselov, K. S. ;

Krishnamurthy, H. R. ;

Geim, A. K. ;

Ferrari, A. C. ;

Sood, A. K. .

NATURE NANOTECHNOLOGY, 2008, 3 (04) :210-215

[8]

Dresselhaus MS, 2002, ADV PHYS, V51, P1, DOI [10.1080/00018730110113644, 10.1080/00018738100101367]

[9] RAMAN-SCATTERING FROM IN-PLANE LATTICE MODES IN LOW-STAGE GRAPHITE-ALKALI-METAL COMPOUNDS [J].

EKLUND, PC ;

DRESSELHAUS, G ;

DRESSELHAUS, MS ;

FISCHER, JE .

PHYSICAL REVIEW B, 1977, 16 (08) :3330-3333

[10] ANALYSIS OF BREIT-WIGNER LINE-SHAPES IN THE RAMAN-SPECTRA OF GRAPHITE-INTERCALATION COMPOUNDS [J].

EKLUND, PC ;

SUBBASWAMY, KR .

PHYSICAL REVIEW B, 1979, 20 (12) :5157-5161

← 1 2 3 4 →