Magnetic-field tuning of photo-induced superconductivity in striped La$_{2-x}$Ba$_x$CuO$_4$
Year: 2018
Type: report
Abstract: Optical excitation of stripe-ordered La2−xBaxCuO4 has been shown to transiently enhance superconducting tunneling between the CuO2 planes. This effect was revealed by a blue-shift, or by the appearance of a Josephson Plasma Resonance in the terahertz-frequency optical properties. Here, we show that this photo-induced state can be strengthened by the application of high external magnetic fields oriented along the c-axis. For a 7-Tesla field, we observe up to a ten-fold enhancement in the transient interlayer phase correlation length, accompanied by a two-fold increase in the relaxation time of the photo-induced state. These observations are highly surprising, since static magnetic fields suppress interlayer Josephson tunneling and stabilize stripe order at equilibrium. We interpret our data as an indication that optically-enhanced interlayer coupling in La2−xBaxCuO4 does not originate from a strengthening of the equilibrium superconductor that competes with stripes, as previously hypothesized. Rather, these results suggest that the photo-induced state may emerge from activated tunneling between optically-excited pair-density-waves in adjacent planes.
Source: Max Planck Digital Library
Authors: D. Nicoletti, D. Fu, Omar Mehio, Steven A. Moore, Ankit Disa, Genda Gu, A. Cavalleri
Language: English
Subfield: Condensed Matter Physics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: green
OpenAlex ID: W2793621749