Ultrafast Evolution of the Excited-State Potential Energy Surface of TiO2 Single Crystals Induced by Carrier Cooling

被引：32

作者：

Bothschafter, Elisabeth M. ^{[1
,2
]}

Paarmann, Alexander ^{[3
]}

Zijlstra, Eeuwe S. ^{[4
]}

Karpowicz, Nicholas ^{[2
]}

Garcia, Martin E. ^{[4
]}

Kienberger, Reinhard ^{[1
,2
]}

Ernstorfer, Ralph ^{[3
]}

机构：

[1] Tech Univ Munich, Dept Phys, D-85748 Garching, Germany

[2] Max Planck Inst Quantum Opt, D-85748 Garching, Germany

[3] Max Planck Gesell, Fritz Haber Inst, D-14195 Berlin, Germany

[4] Univ Kassel, D-34132 Kassel, Germany

来源：

PHYSICAL REVIEW LETTERS | 2013年 / 110卷 / 06期

关键词：

COHERENT; DYNAMICS; PHONONS; BISMUTH;

D O I：

10.1103/PhysRevLett.110.067402

中图分类号：

O4 [物理学];

学科分类号：

0702 ;

摘要：

We investigate the influence of carrier cooling dynamics in TiO2 on the excited-state potential energy surface along the A(1g) optical phonon coordinate after above band-gap excitation using ultrashort ultraviolet pulses. The large amplitude coherent oscillation observed in a pump-probe transient reflectivity measurement shows a phase shift of -0.2 pi with respect to a purely instantaneous displacive excitation. The dynamic evolution of the potential energy surface minimum of the coherent phonon coordinate is explored using accurate density functional theory calculations, which confirm a shift of the potential energy surface minimum upon resonant laser excitation and reveal a significant positive contribution to the displacive force due to the cooling of the excited hot electron-hole plasma. We show that this noninstantaneous effect can quantitatively explain the experimentally observed phase using reasonable assumptions for the parameters characterizing the excited carriers. Our work demonstrates that the fast equilibration dynamics of laser-excited nonequilibrium carrier populations can have a pronounced effect on the initial structural response of crystalline solids. DOI: 10.1103/PhysRevLett.110.067402

引用

页数：5

共 23 条

[1]

Blaha P., 2001, CALCULATING CRYST PR, V60

[2] Collinear generation of ultrashort UV and XUV pulses [J].

Bothschafter, E. M. ;

Schiffrin, A. ;

Yakovlev, V. S. ;

Azzeer, A. M. ;

Krausz, F. ;

Ernstorfer, R. ;

Kienberger, R. .

OPTICS EXPRESS, 2010, 18 (09) :9173-9180

[3] Self-energy and excitonic effects in the electronic and optical properties of TiO2 crystalline phases [J].

Chiodo, Letizia ;

Maria Garcia-Lastra, Juan ;

Iacomino, Amilcare ;

Ossicini, Stefano ;

Zhao, Jin ;

Petek, Hrvoje ;

Rubio, Angel .

PHYSICAL REVIEW B, 2010, 82 (04)

[4]

Dekorsy T, 2000, TOP APPL PHYS, V76, P169

[5] Quantum dynamical study of the amplitude collapse and revival of coherent A 1g phonons in bismuth: a classical phenomenon? [J].

Diakhate, Momar S. ;

Zijlstra, Eeuwe S. ;

Garcia, Martin E. .

APPLIED PHYSICS A-MATERIALS SCIENCE & PROCESSING, 2009, 96 (01) :5-10

[6] Photoinduced structural dynamics of polar solids studied by femtosecond X-ray diffraction [J].

Elsaesser, Thomas ;

Woerner, Michael .

ACTA CRYSTALLOGRAPHICA SECTION A, 2010, 66 :168-178

[7] Ultrafast bond softening in bismuth:: Mapping a solid's interatomic potential with X-rays [J].

Fritz, D. M. ;

Reis, D. A. ;

Adams, B. ;

Akre, R. A. ;

Arthur, J. ;

Blome, C. ;

Bucksbaum, P. H. ;

Cavalieri, A. L. ;

Engemann, S. ;

Fahy, S. ;

Falcone, R. W. ;

Fuoss, P. H. ;

Gaffney, K. J. ;

George, M. J. ;

Hajdu, J. ;

Hertlein, M. P. ;

Hillyard, P. B. ;

Hoegen, M. Horn-von ;

Kammler, M. ;

Kaspar, J. ;

Kienberger, R. ;

Krejcik, P. ;

Lee, S. H. ;

Lindenberg, A. M. ;

McFarland, B. ;

Meyer, D. ;

Montagne, T. ;

Murray, E. D. ;

Nelson, A. J. ;

Nicoul, M. ;

Pahl, R. ;

Rudati, J. ;

Schlarb, H. ;

Siddons, D. P. ;

Sokolowski-Tinten, K. ;

Tschentscher, Th. ;

von der Linde, D. ;

Hastings, J. B. .

SCIENCE, 2007, 315 (5812) :633-636

[8] The birth of a quasiparticle in silicon observed in time-frequency space [J].

Hase, M ;

Kitajima, M ;

Constantinescu, AM ;

Petek, H .

NATURE, 2003, 426 (6962) :51-54

[9] Electron transport in TiO2 probed by THz time-domain spectroscopy -: art. no. 081101 [J].

Hendry, E ;

Wang, F ;

Shan, J ;

Heinz, TF ;

Bonn, M .

PHYSICAL REVIEW B, 2004, 69 (08)

[10] Ultrafast electron dynamics at Cu(111): Response of an electron gas to optical excitation [J].

Hertel, T ;

Knoesel, E ;

Wolf, M ;

Ertl, G .

PHYSICAL REVIEW LETTERS, 1996, 76 (03) :535-538

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