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Title: Large Polarons as Key Quasiparticles in SrTiO3 and SrTiO3-Based Heterostructures

Abstract

Despite its simple structure and low degree of electronic correlation, SrTiO 3 (STO) features collective phenomena linked to charge transport and, ultimately, superconductivity, that are not yet fully explained. Thus, a better insight into the nature of the quasiparticles shaping the electronic and conduction properties of STO is needed. We studied the low-energy excitations of bulk STO and of the LaAlO 3 / SrTiO 3 two-dimensional electron gas (2DEG) by Ti L 3 edge resonant inelastic x-ray scattering. In all samples, we find the hallmark of polarons in the form of intense d d + phonon excitations, and a decrease of the LO3-mode electron-phonon coupling when going from insulating to highly conducting STO single crystals and heterostructures. Overall, both results are attributed to the dynamic screening of the large polaron self-induced polarization, showing that the low-temperature physics of STO and STO-based 2DEGs is dominated by large polaron quasiparticles.

Authors:
 [1];  [2];  [3];  [3];  [3];  [4]; ORCiD logo [5]; ORCiD logo [6];  [7];  [1];  [8];  [9]; ORCiD logo [10]; ORCiD logo [2]
  1. European Synchrotron Radiation Facility (ESRF), Grenoble (France)
  2. CNR-SPIN Complesso Monte-Santangelo, Napoli (Italy)
  3. CNR-SPIN Complesso Monte-Santangelo, Napoli (Italy); Univ. di Napoli (Italy)
  4. European Synchrotron Radiation Facility (ESRF), Grenoble (France); Max Planck Inst. für Festkörperforschung, Stuttgart (Germany)
  5. Politecnico di Milano (Italy); SLAC National Accelerator Lab., Menlo Park, CA (United States). Stanford Institute for Materials and Energy Science (SIMES)
  6. Politecnico di Milano (Italy); Peking Univ., Beijing (China)
  7. Politecnico di Milano (Italy)
  8. European Synchrotron Radiation Facility (ESRF), Grenoble (France); Politecnico di Milano (Italy)
  9. European Synchrotron Radiation Facility (ESRF), Grenoble (France); Brookhaven National Lab. (BNL), Upton, NY (United States)
  10. Politecnico di Milano (Italy); CNR-SPIN, Milano (Italy)
Publication Date:
Research Org.:
Brookhaven National Lab. (BNL), Upton, NY (United States)
Sponsoring Org.:
USDOE Office of Science (SC), Basic Energy Sciences (BES); MIUR; EU Horizon 2020; Regione Lombardia
OSTI Identifier:
1668633
Report Number(s):
BNL-219851-2020-JAAM
Journal ID: ISSN 0031-9007
Grant/Contract Number:  
SC0012704; 731473; PRIN 20177SL7HC; PRIN 2017Z8TS5B; 2016-0790
Resource Type:
Accepted Manuscript
Journal Name:
Physical Review Letters
Additional Journal Information:
Journal Volume: 125; Journal Issue: 12; Journal ID: ISSN 0031-9007
Publisher:
American Physical Society (APS)
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; Electronic structure; optical phonons; polarons; heterostructures; single crystal materials; superlattices; two-dimensional electron system; crystal-field theory; resonant inelastic x-ray scattering

Citation Formats

Geondzhian, Andrey, Sambri, Alessia, De Luca, Gabriella M., Di Capua, Roberto, Di Gennaro, Emiliano, Betto, Davide, Rossi, Matteo, Peng, Ying Ying, Fumagalli, Roberto, Brookes, Nicholas B., Braicovich, Lucio, Gilmore, Keith, Ghiringhelli, Giacomo, and Salluzzo, Marco. Large Polarons as Key Quasiparticles in SrTiO3 and SrTiO3-Based Heterostructures. United States: N. p., 2020. Web. https://doi.org/10.1103/physrevlett.125.126401.
Geondzhian, Andrey, Sambri, Alessia, De Luca, Gabriella M., Di Capua, Roberto, Di Gennaro, Emiliano, Betto, Davide, Rossi, Matteo, Peng, Ying Ying, Fumagalli, Roberto, Brookes, Nicholas B., Braicovich, Lucio, Gilmore, Keith, Ghiringhelli, Giacomo, & Salluzzo, Marco. Large Polarons as Key Quasiparticles in SrTiO3 and SrTiO3-Based Heterostructures. United States. https://doi.org/10.1103/physrevlett.125.126401
Geondzhian, Andrey, Sambri, Alessia, De Luca, Gabriella M., Di Capua, Roberto, Di Gennaro, Emiliano, Betto, Davide, Rossi, Matteo, Peng, Ying Ying, Fumagalli, Roberto, Brookes, Nicholas B., Braicovich, Lucio, Gilmore, Keith, Ghiringhelli, Giacomo, and Salluzzo, Marco. Tue . "Large Polarons as Key Quasiparticles in SrTiO3 and SrTiO3-Based Heterostructures". United States. https://doi.org/10.1103/physrevlett.125.126401. https://www.osti.gov/servlets/purl/1668633.
@article{osti_1668633,
title = {Large Polarons as Key Quasiparticles in SrTiO3 and SrTiO3-Based Heterostructures},
author = {Geondzhian, Andrey and Sambri, Alessia and De Luca, Gabriella M. and Di Capua, Roberto and Di Gennaro, Emiliano and Betto, Davide and Rossi, Matteo and Peng, Ying Ying and Fumagalli, Roberto and Brookes, Nicholas B. and Braicovich, Lucio and Gilmore, Keith and Ghiringhelli, Giacomo and Salluzzo, Marco},
abstractNote = {Despite its simple structure and low degree of electronic correlation, SrTiO3 (STO) features collective phenomena linked to charge transport and, ultimately, superconductivity, that are not yet fully explained. Thus, a better insight into the nature of the quasiparticles shaping the electronic and conduction properties of STO is needed. We studied the low-energy excitations of bulk STO and of the LaAlO3/SrTiO3 two-dimensional electron gas (2DEG) by Ti L3 edge resonant inelastic x-ray scattering. In all samples, we find the hallmark of polarons in the form of intense dd+phonon excitations, and a decrease of the LO3-mode electron-phonon coupling when going from insulating to highly conducting STO single crystals and heterostructures. Overall, both results are attributed to the dynamic screening of the large polaron self-induced polarization, showing that the low-temperature physics of STO and STO-based 2DEGs is dominated by large polaron quasiparticles.},
doi = {10.1103/physrevlett.125.126401},
journal = {Physical Review Letters},
number = 12,
volume = 125,
place = {United States},
year = {2020},
month = {9}
}

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Works referenced in this record:

A high-mobility electron gas at the LaAlO3/SrTiO3 heterointerface
journal, January 2004


Superconducting Interfaces Between Insulating Oxides
journal, August 2007


Occurrence of a high-temperature superconducting phase in (CaCuO 2 ) n /(SrTiO 3 ) m superlattices
journal, October 2012


Interface-Induced High-Temperature Superconductivity in Single Unit-Cell FeSe Films on SrTiO 3
journal, March 2012


Superconductivity above 100 K in single-layer FeSe films on doped SrTiO3
journal, November 2014

  • Ge, Jian-Feng; Liu, Zhi-Long; Liu, Canhua
  • Nature Materials, Vol. 14, Issue 3
  • DOI: 10.1038/nmat4153

Interfacial mode coupling as the origin of the enhancement of Tc in FeSe films on SrTiO3
journal, November 2014

  • Lee, J. J.; Schmitt, F. T.; Moore, R. G.
  • Nature, Vol. 515, Issue 7526
  • DOI: 10.1038/nature13894

Effect of the 110°K Phase Transition on the SrTi O 3 Conduction Bands
journal, December 1972


Theory of spin-orbit coupling at LaAlO 3 /SrTiO 3 interfaces and SrTiO 3 surfaces
journal, April 2013


Orbital Reconstruction and the Two-Dimensional Electron Gas at the LaAlO3/SrTiO3 Interface
journal, April 2009


Doping-dependent band structure of LaAlO 3 /SrTiO 3 interfaces by soft x-ray polarization-controlled resonant angle-resolved photoemission
journal, March 2014


Electron-Phonon Interaction and Charge Carrier Mass Enhancement in SrTiO 3
journal, June 2008


Common Fermi-liquid origin of T 2 resistivity and superconductivity in n -type SrTiO 3
journal, November 2011


Strong energy–momentum dispersion of phonon-dressed carriers in the lightly doped band insulator SrTiO 3
journal, February 2010


Many-body large polaron optical conductivity in SrTi 1 x Nb x O 3
journal, March 2010


Optical Response of an Interacting Polaron Gas in Strongly Polar Crystals
journal, March 2020

  • Klimin, Serghei; Tempere, Jacques; Devreese, Jozef T.
  • Applied Sciences, Vol. 10, Issue 6
  • DOI: 10.3390/app10062059

Mechanism of superconductivity in SrTiO3
journal, August 1981


Soft-Mode Superconductivity in SrTi O 3 x
journal, April 1969


Interface superconductivity in LaAlO 3 SrTiO 3 heterostructures
journal, May 2014


Quantum Critical Origin of the Superconducting Dome in SrTiO 3
journal, December 2015


The beamline ID32 at the ESRF for soft X-ray high energy resolution resonant inelastic X-ray scattering and polarisation dependent X-ray absorption spectroscopy
journal, September 2018

  • Brookes, N. B.; Yakhou-Harris, F.; Kummer, K.
  • Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, Vol. 903
  • DOI: 10.1016/j.nima.2018.07.001

Electron-Phonon Coupling in the Bulk of Anatase TiO 2 Measured by Resonant Inelastic X-Ray Spectroscopy
journal, August 2015


Hybridization and electron-phonon coupling in ferroelectric BaTiO 3 probed by resonant inelastic x-ray scattering
journal, November 2016


Localized and delocalized Ti 3 d carriers in LaAlO 3 /SrTiO 3 superlattices revealed by resonant inelastic x-ray scattering
journal, May 2011


Raman and fluorescence contributions to the resonant inelastic soft x-ray scattering on LaAlO 3 / SrTiO 3 heterostructures
journal, January 2018


Generalized Franck-Condon principle for resonant photoemission
journal, October 1999


QUANTUM ESPRESSO: a modular and open-source software project for quantum simulations of materials
journal, September 2009

  • Giannozzi, Paolo; Baroni, Stefano; Bonini, Nicola
  • Journal of Physics: Condensed Matter, Vol. 21, Issue 39, Article No. 395502
  • DOI: 10.1088/0953-8984/21/39/395502

EDRIXS: An open source toolkit for simulating spectra of resonant inelastic x-ray scattering
journal, October 2019


Atomic Control of the SrTiO3 Crystal Surface
journal, December 1994


Quasi-ideal strontium titanate crystal surfaces through formation of strontium hydroxide
journal, November 1998

  • Koster, Gertjan; Kropman, Boike L.; Rijnders, Guus J. H. M.
  • Applied Physics Letters, Vol. 73, Issue 20
  • DOI: 10.1063/1.122630

Ti- and Sr-rich surfaces of SrTiO3 studied by grazing incidence x-ray diffraction
journal, September 2007

  • Fragneto, A.; De Luca, G. M.; Di Capua, R.
  • Applied Physics Letters, Vol. 91, Issue 10
  • DOI: 10.1063/1.2779972

Interface superconductivity
journal, July 2015


Mapping the spatial distribution of charge carriers in LaAlO3/SrTiO3 heterostructures
journal, June 2008

  • Basletic, M.; Maurice, J. -L.; Carrétéro, C.
  • Nature Materials, Vol. 7, Issue 8
  • DOI: 10.1038/nmat2223

Efficient implementation of core-excitation Bethe–Salpeter equation calculations
journal, December 2015


High-throughput density-functional perturbation theory phonons for inorganic materials
journal, May 2018

  • Petretto, Guido; Dwaraknath, Shyam; P. C. Miranda, Henrique
  • Scientific Data, Vol. 5, Issue 1
  • DOI: 10.1038/sdata.2018.65

Polaronic metal state at the LaAlO3/SrTiO3 interface
journal, January 2016

  • Cancellieri, C.; Mishchenko, A. S.; Aschauer, U.
  • Nature Communications, Vol. 7, Issue 1
  • DOI: 10.1038/ncomms10386

Numerical quantification of the vibronic broadening of the SrTiO 3 Ti L-edge spectrum
journal, July 2010


Relativistic cluster calculation of ligand-field multiplet effects on cation L 2 , 3 x -ray-absorption edges of SrTiO 3 , NiO, and CaF 2
journal, August 2001


Determining the electron-phonon coupling strength from Resonant Inelastic X-ray Scattering at transition metal L-edges
journal, July 2011

  • Ament, L. J. P.; van Veenendaal, M.; van den Brink, J.
  • EPL (Europhysics Letters), Vol. 95, Issue 2
  • DOI: 10.1209/0295-5075/95/27008

Generalization of the Franck-Condon model for phonon excitations by resonant inelastic x-ray scattering
journal, June 2020


Natural widths of atomic K and L levels, K α X‐ray lines and several K L L Auger lines
journal, April 1979

  • Krause, M. O.; Oliver, J. H.
  • Journal of Physical and Chemical Reference Data, Vol. 8, Issue 2
  • DOI: 10.1063/1.555595

Polaronic behavior in a weak-coupling superconductor
journal, January 2018

  • Swartz, Adrian G.; Inoue, Hisashi; Merz, Tyler A.
  • Proceedings of the National Academy of Sciences, Vol. 115, Issue 7
  • DOI: 10.1073/pnas.1713916115

Tailoring the nature and strength of electron–phonon interactions in the SrTiO3(001) 2D electron liquid
journal, April 2016

  • Wang, Z.; McKeown Walker, S.; Tamai, A.
  • Nature Materials, Vol. 15, Issue 8
  • DOI: 10.1038/nmat4623

Pseudo Jahn–Teller effect in the origin of enhanced flexoelectricity
journal, January 2015


Polarons from First Principles, without Supercells
journal, June 2019