Light-induced orbital magnetism in metals via inverse Faraday effect

We present a microscopic calculation of the inverse Faraday effect in metals. We derive a static local magnetic moment induced on the application of high-frequency light, using the Eilenberger formulation of quasiclassical theory. We include the effect of disorder and formulate a theory applicable across the entire temperature range, in the absence of external applied fields. For light-induced electric fields of amplitude <a:math xmlns:a="http://www.w3.org/1998/Math/MathML"><a:mrow><a:mo>∼</a:mo><a:mn>100</a:mn><a:mspace width="0.16em"/><a:mtext>kV/cm</a:mtext></a:mrow></a:math>, the induced fields are large <c:math xmlns:c="http://www.w3.org/1998/Math/MathML"><c:mrow><c:mo>∼</c:mo><c:mn>0.1</c:mn><c:mspace width="0.16em"/><c:mtext>T</c:mtext></c:mrow></c:math> for metallic Nb. The predictions of our theory agree with recent experimental and theoretical results [O. H.-C. Cheng , and J. Hurst , ]. An extension of this approach to superconductors would open a new route of inducing orbital magnetic field and potentially vortices in superconductors.