ZhETF, Vol. 143,
p. 977 (May 2013)
(English translation - JETP,
Vol. 116, No. 5,
available online at www.springer.com
STRONGLY CORRELATED QUANTUM SPIN LIQUID IN HERBERTSMITHITE
Shaginyan V.R., Popov K.G., Khodel V.A.
Received: August 29, 2012
Strongly correlated Fermi systems are among the most intriguing and fundamental systems in physics. We show that the herbertsmithite can be regarded as a new type of strongly correlated electrical insulator that possesses properties of heavy-fermion metals with one exception: it resists the flow of electric charge. We demonstrate that herbertsmithite's low-temperature properties are defined by a strongly correlated quantum spin liquid made with hypothetic particles such as fermionic spinons that carry spin 1/2 and no charge. Our calculations of its thermodynamic and relaxation properties are in good agreement with recent experimental facts and allow us to reveal their scaling behavior, which strongly resembles that observed in heavy-fermion metals. Analysis of the dynamic magnetic susceptibility of strongly correlated Fermi systems suggests that there exist at least two types of its scaling.