Zurab Guguchia Physik-Institut der Universität Zürich, Winterthurerstrasse 190,
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photons muons neutro ns Tuning the static spin- stripe phase and superconductivity in La 2- x Ba x CuO 4 (x = 1/8) by hydrostatic pressure Zurab Guguchia Physik-Institut der Universität Zürich, Winterthurerstrasse 190, CH-8057 Zürich, Switzerland
description
neutrons. muons. photons. Tuning the static spin-stripe phase and superconductivity in La 2- x Ba x CuO 4 ( x = 1/8) by hydrostatic pressure. Zurab Guguchia Physik-Institut der Universität Zürich, Winterthurerstrasse 190, CH-8057 Zürich, Switzerland. Tbilisi State University. - PowerPoint PPT Presentation
Transcript of Zurab Guguchia Physik-Institut der Universität Zürich, Winterthurerstrasse 190,
photons
muons
neutrons
Tuning the static spin-stripe phase and superconductivity in La2-xBaxCuO4 (x =
1/8) by hydrostatic pressure
Zurab Guguchia
Physik-Institut der Universität Zürich, Winterthurerstrasse 190, CH-8057 Zürich, Switzerland
Thank you!Thank you!
University of Zürich in collaboration with:
• Tbilisi State University, Georgia
• Paul Scherrer Institute (PSI), Switzerland
Tbilisi State University
Superconductivity in La2-xBaxCuO4
J. D. Axe et. al., Phys. Rev. Lett. 62, 2751 (1989).
M. Hücker et. al., Phys. Rev. B 83, 104506 (2011).
TLTO→LTT ≈ 50 KTHTT→LTO ≈ 200 K
A. R. Moodenbaugh et. al., Phys. Rev. B 38, 4596 (1988).
1/8 problem
LTO
0.11 < x ≤ 0.13
Stripe order in cuprate superconductors
K.A. Moler, Nature 468, 643-644 (2010).
J. Zaanen, PRB 40, 7391 (1989).
La1.48Nd0.4Sr0.12CuO4
J.M. Tranquada et. al., Nature (London) 375, 561 (1995).
Stripe order in La1.875Ba0.125CuO4
M. Hücker et. al., Phys. Rev. B 83, 104506 (2011).
High-pressure studies on La1.875Ba0.125CuO4 have suggested that Tc of the system is restored under high pressure.
Tso vs hydrostatic pressure?
Superconducting properties of La1.875Ba0.125CuO4
Diamond anvil cell for high-pressure measurements
TRIUMF http://neutron.magnet.fsu.edu/muon_relax.html
Muon-spin rotation (μSR) technique
Courtesy of H. Luetkens
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μSR in magnetic materials
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High pressure µSR experiments on La1.875Ba0.125CuO4
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D. Andreica, Ph.D. thesis, IPP/ETH-Zürich, (2001).
High pressure µSR experiments on La1.875Ba0.125CuO4
Phase diagrams
Conclusions
The interplay between magnetism and superconductivity was studied in La1.875Ba0.125CuO4 as a function of pressure up to p ≈ 2.25 GPa.
At p = 0 static spin-stripe order is stabilized below Tso = 32 K, occupies nearly the whole sample volume and superconductivity exists in a minor part of the sample only.
The ordered moment size and the magnetic ordering temperature does not change upon application of pressure. However, the volume fraction of spin-stripe order significantly decreases with increasing p.
At the same time by the application of pressure SC phase volume increases proportionally to the non-magnetic volume fraction.
These results indicate that in La1.875Ba0.125CuO4 magnetism and superconductivity occur in mutually exclusive spatial regions.
Thank you very much for your attention!Thank you very much for your attention!
