The Elusive Bose Metal
Philip Phillips1* and
Denis Dalidovich2
The conventional theory of metals is in crisis. In the past
15 years, there has been an unexpected sprouting of metallic
states in low-dimensional systems, directly contradicting conventional
wisdom. For example, bosons are thought to exist in one of two
ground states: condensed in a superconductor or localized in
an insulator. However, several experiments on thin metal-alloy
films have observed that a metallic phase disrupts the direct
transition between the superconductor and the insulator. We
analyze the experiments on the insulator-superconductor transition
and argue that the intervening metallic phase is bosonic. All
relevant theoretical proposals for the Bose metal are discussed,
particularly the recent idea that the metallic phase is glassy.
The implications for the putative vortex-glass state in the
copper oxide superconductors are examined.
2 National High Magnetic Field Laboratory, Florida State University, Tallahassee, FL 32310, USA.
* To whom correspondence should be addressed. E-mail: dimer{at}uiuc.edu
