Metal–insulator crossover in high 𝑇c cuprates: A gauge field approach

Pramana

Z B Su²  P A Marchetti1¹  L Yu2² 

[1]Dipartimento di Fisica ‘G.Galilei’ and INFN-Sez. di Padova, Italy$$

[2]Institute of Theoretical Physics, CAS Beijing 100080, China$$

关键词: Resistivity;    crossover;    t-J.;   

DOI  :  

学科分类：物理（综合）

来源: Indian Academy of Sciences

【 摘 要 】

A metal–insulator crossover appears in the experimental data for in-plane resistivity of underdoped cuprates and a range of superconducting cuprates in the presence of a strong magnetic field suppressing superconductivity. We propose an explanation for this phenomenon based on a gauge field theory approach to the t-J model. In this approach, based on a formal spin-charge separation, the low energy effective action describes gapful spinons (with a theoretically derived doping dependence of the gap $m^{2}_{s}∼𝛿|{m ln }𝛿|$) and holons with finite Fermi surface (𝜖F ∼ 𝑡𝛿) interacting via a gauge field whose basic effect on the spinons is to bind them into overdamped spin waves, shifting their gap by a damping term linear in 𝑇, which causes the metal–insulator crossover. The presence of a magnetic field perpendicular to the plane acts by increasing the damping, in turn producing a big positive transverse in-plane magnetoresistance at low 𝑇, as experimentally observed.

【 授权许可】

Unknown