Optical Saturation Produces Spurious Evidence for Photoinduced Superconductivity in<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:mrow><mml:msub><mml:mrow><mml:mi mathvariant="normal">K</mml:mi></mml:mrow><mml:mrow><mml:mn>3</mml:mn></mml:mrow></mml:msub><mml:msub><mml:mrow><mml:mi mathvariant="normal">C</mml:mi></mml:mrow><mml:mrow><mml:mn>60</mml:mn></mml:mrow></mml:msub></mml:mrow></mml:math>
J. Steven Dodge, Leya Lopez, Derek G. Sahota
Abstract
We discuss a systematic error in time-resolved optical conductivity measurements that becomes important at high pump intensities. We show that common optical nonlinearities can distort the photoconductivity depth profile, and by extension distort the photoconductivity spectrum. We show evidence that this distortion is present in existing measurements on K_{3}C_{60}, and describe how it may create the appearance of photoinduced superconductivity where none exists. Similar errors may emerge in other pump-probe spectroscopy measurements, and we discuss how to correct for them.
Topics & Concepts
Spurious relationshipPhotoconductivitySaturation (graph theory)PhysicsSpectroscopySuperconductivityDistortion (music)Electrical resistivity and conductivityOptical conductivityCondensed matter physicsOpticsComputer scienceOptoelectronicsMathematicsMachine learningQuantum mechanicsCombinatoricsCMOSAmplifierQuantum and electron transport phenomenaPhysics of Superconductivity and MagnetismDiamond and Carbon-based Materials Research