Historical research guide · 0916 · 2011

Light-Induced Superconductivity in a Stripe-Ordered Cuprate

D. Fausti · R. I. Tobey · N. Dean · S. Kaiser · A. Dienst · M. C. Hoffmann · S. Pyon · T. Takayama · H. Takagi · A. Cavalleri

In one minute

Some copper-oxide compounds refuse to superconduct because their electrons lock into stripes — alternating one-dimensional lanes of spin and charge that hold the material rigid. Fausti, Tobey, Dean and colleagues in Andrea Cavalleri’s group hit one of those compounds, a lanthanum-europium-strontium copper oxide that does not superconduct at all, with a femtosecond pulse of mid-infrared light. For a moment afterwards it is a superconductor, and not a single-layer one: current moves coherently between the copper-oxide planes as well as within them, which makes it three-dimensional. They know because a Josephson plasma resonance appears promptly in the material’s optical response along the stacking axis, the fingerprint of coherent tunnelling from layer to layer. The striking number is the clock. The superconducting phase assembles within one to two picoseconds at most, far faster than anyone expected it could. That speed is the result’s teeth: it puts hard new limits on what stripe order can be and on how it is related to superconductivity.

Connection

Chapter 11 treats superconductors as the material where the most interesting effects are looked for, and this is the demonstration that superconductivity itself can be switched on by light in a compound that does not have it — a property of matter driven into existence rather than doped in. Chapter 2 keeps the ledger of what a driven electromagnetic field can be made to do to a medium, and a single infrared pulse turning a striped, non-superconducting crystal into a three-dimensional superconductor belongs on that ledger.

From the source

One of the most intriguing features of some high-temperature cuprate superconductors is the interplay between one-dimensional striped spin order and charge order on the one hand, and superconductivity on the other.Abstract, first sentence
The starting material is chosen precisely because it does not superconduct: La1.675Eu0.2Sr0.125CuO4, a stripe-ordered cuprate in its nonsuperconducting state.Abstract, second sentence
Mid-infrared femtosecond pulses transform that compound into a transient three-dimensional superconductor — the superconductivity is induced by the light, not present beforehand.Abstract, second sentence
The evidence for the claim is a specific optical signature: the emergence of coherent interlayer transport is evidenced by the prompt appearance of a Josephson plasma resonance in the c-axis optical properties, which is the response of coherent tunnelling between the copper-oxide planes.Abstract, third sentence
An upper limit for the time scale needed to form the superconducting phase is estimated at 1 to 2 picoseconds, which the authors state is significantly faster than expected.Abstract, fourth sentence
The consequence the authors draw is theoretical rather than technological: the speed of formation places stringent new constraints on our understanding of stripe order and its relation to superconductivity, which is the question the follow-up experiments are aimed at.Abstract, closing sentence

The way in

https://doi.org/10.1126/science.1197294

Historical source-access record. This guide links to the original; it does not reproduce the paper text.

SOURCE NOT REACHED IN FULL. The article is held by AAAS as Science volume 331, pages 189 to 191, and Crossref carries no licence statement for it. On 2026-09-08 an open copy was looked for and not found: arXiv returns no preprint under this title, and a search of the Cavalleri group’s arXiv record for stripe-phase work returns their later papers from 2013 onward but not this one; OpenAlex and Unpaywall both report open access status closed with no repository location; Semantic Scholar records the same and states that the publisher has elided the abstract from its record; Europe PMC holds the PubMed record, 21233381, and reports it neither open access nor in Europe PMC. The status was raised from summary-only to abstract-only because the authors’ own complete abstract is carried, identically, by two independent bibliographic records — OpenAlex and Europe PMC — and it is that abstract which is reproduced below and which the summary and every claim are written from; the locators therefore all say Abstract, because the abstract is what was read. FORMULA. The abstract is reproduced exactly as those records carry it, including the plain-text rendering of the compound as La(1.675)Eu(0.2)Sr(0.125)CuO(4); in the journal those numbers are set as subscripts, and the parentheses are a transcription artefact of the record, not the authors’ notation. AUTHORS. Initials are left unexpanded except where a bibliographic authority names the person directly. The work is from the Max Planck Research Department for Structural Dynamics at the University of Hamburg, the Department of Physics at the University of Oxford, and the Department of Advanced Materials at the University of Tokyo.

How to cite it

D. Fausti, R. I. Tobey, N. Dean, S. Kaiser, A. Dienst, M. C. Hoffmann, S. Pyon, T. Takayama, H. Takagi, A. Cavalleri (2011) Light-Induced Superconductivity in a Stripe-Ordered Cuprate doi:10.1126/science.1197294

Where it sits in the curriculum

Gravity control and superconductors