"Emerging coherence with unified energy, temperature, and lifetime scale in heavy fermion YbRh2Si2"

S.-K. Mo: W. S. Lee, F. Schmitt, Y. L. Chen, D. H. Lu, C. Capan, D. J. Kim, Z. Fisk, C.-Q. Zhang, Z. Hussain, and Z.-X. Shen; Physical Review B, 06/22/12.

Additional Authors: W. S. Lee, F. Schmitt, Y. L. Chen, D. H. Lu, C. Capan, D. J. Kim, Z. Fisk, C.-Q. Zhang, Z. Hussain, and Z.-X. Shen

Abstract:

We present ultrahigh resolution angle-resolved photoemission data of the prototypical Kondo lattice system
YbRh2Si2, using a 7 eV laser photon source. Detailed temperature dependent measurements reveal the
development of coherent states, in the form of sharp, weakly dispersing peaks at the lowest energy of
single-electron spectra, below a characteristic temperature. The characteristic temperature, obtained from
angle-resolved photoemission, is intriguingly of exactly the same scale as the energy and the lifetime of the coherent state.