Anomalous density-of-states fluctuations in two-dimensional clean metals
1 Institute for Physical Science and Technology and Department of Physics, University of Maryland College Park, MD 20742, USA
2 Department of Physics and Theoretical Science Institute, University of Oregon - Eugene, OR 97403, USA
Received: 23 January 2013
Accepted: 12 March 2013
It is shown that density-of-states fluctuations, which can be interpreted as the order-parameter susceptibility χOP in a Fermi liquid, are anomalously strong as a result of the existence of Goldstone modes and associated strong fluctuations. In a 2-d system with a long-ranged Coulomb interaction, a suitably defined χOP diverges as 1/T2 as a function of the temperature in the limit of small wave number and frequency. In contrast, standard statistics suggest χOP = O(T), a discrepancy of three powers of T. The reasons behind this surprising prediction, as well as ways to observe it, are discussed.
PACS: 71.27.+a – Strongly correlated electron systems; heavy fermions / 71.20.-b – Electron density of states and band structure of crystalline solids / 73.40.Gk – Tunneling
© EPLA, 2013