Charge pair hopping and Bose-Einstein condensation in underdoped Mott insulators

Article

关键词: HIGH-TEMPERATURE SUPERCONDUCTORS;    HIGH-TC SUPERCONDUCTIVITY;    VALENCE-BOND STATE;    QUANTUM ANTIFERROMAGNET;    SPIRAL STATES;    J MODEL;    SEPARATION;    SYSTEMS;    FIELD;    HOLES;   

DOI  :  10.1103/PhysRevB.85.144502

来源: SCIE

【 摘 要 】

Recently, a renormalized Hamiltonian has been derived by continuing spin states from the Mott limit of the t-J model to the underdoped region. We show that it naturally leads to a pairing mechanism in which the pair has a dual character. Its spin part is a spinon singlet that condenses at T*. The charge part is a real-space holon pair formed at T-p < T*, which undergoes a Bose-Einstein condensation at T-c < T-p. While neither is observable separately, the combination is predicted to be observable as a sharp excitation above and below T-c. The mechanism is consistent with the small superfluid density, the decline of T-c at small doping, and the existence of pairs above T-c in cuprates, indicated by the observation of diamagnetism and Nernst effect.

【 授权许可】

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