nanoGUNE Colloquium: Probing correlated electron matter by infrared nano-spectroscopy and nano-imaging
CIC nanoGUNE Seminars
- Speaker
-
Prof. D.N. Basov, University of California San Diego
- When
-
2013/07/08
13:00 - Place
- nanoGUNE seminar room, Tolosa Hiribidea 76, Donostia - San Sebastian
- Add to calendar
- iCal
**Host** : Txema Pitarke
One common attribute of several classes of correlated electron systems is that
the insulator-to-metal transition in these systems typically occurs in the
regime of nano-scale phase separation of chemical, and/or electronic/magnetic
origin [1]. These intrinsic non-uniformities complicate the inquiry into the
roles of lattice/structural transformations and many body physics in the
emergence of metallicity. Despite rapid progress with the development of
scanning probe techniques, it remains a challenging task to _simultaneously_
probe nano-scale variations of electronic and structural properties over
macroscopic regions [2]. We have accomplished this task using advanced nano-
infrared methods that we have applied to investigate crystalline films of a
prototypical correlated oxide VO2. Recent experiments [3] have allowed us to
visualize the route cause of the electronic anisotropy and memory effects [4]
in this material. Through nano-spectroscopic monitoring of the lattice and
free carrier dynamics in VO2 we uncovered three different stages of the
insulator-to-metal transition characterized by distinct electron-lattice
effects.
[1] D. N. Basov, Richard D. Averitt, Dirk van der Marel, Martin Dressel, and
Kristjan Haule “[ _Electrodynamics of correlated electron
materials_](http://rmp.aps.org/abstract/RMP/v83/i2/p471_1) †Reviews of
Modern Physics 83, 471 (2011)
[2] Dawn A. Bonnell, D. N. Basov, Matthias Bode, Ulrike Diebold, Sergei V.
Kalinin, Vidya Madhavan, Lukas Novotny, Miquel Salmeron, Udo D. Schwarz, and
Paul S. Weiss “[ _Imaging physical phenomena with local probes: From
electrons to photons_](http://link.aps.org/doi/10.1103/RevModPhys.84.1343)â€
Reviews of Modern Physics 84, 1343 (2012).
[3] Mengkun Liu, Martin Wagner, Elsa Abreu, Salinporn Kittiwatanakul,
Alexander McLeod, Zhe Fei, Michael Goldflam, Siyuan Dai, Michael Fogler, Jiwei
Lu, Stuart A. Wolf, Richard D. Averitt, D. N. Basov, “Anisotropic electronic
state via spontaneous phase separation in strained Vanadium Dioxide filmsâ€
(under review).
[4] T.Driscoll, H.T. Kim, B.G. Chae, B.J. Kim, N. Marie Jokerst, S. Palit,
D.R. Smith, M. Di Ventra, D.N. Basov “ _Memory Metamaterials_ †Science
325, 1518 (2009).
D.N. Basov, University of California San Diego