Naslov
Low frequency response of superconducting fluctuations in La2-xSrxCuO4

Autori
Grbić, Mihael Srđan ; Peligrad, Dragos ; Požek, Miroslav ; Sasagawa, Takao ; Greven, Martin ; Barišić, Neven ; Dulčić, Antonije

Vrsta, podvrsta i kategorija rada
Sažeci sa skupova, sažetak, znanstveni

Skup
International Conference on Materials and Mechanisms of Superconductivity (M2S 2012)

Mjesto i datum
Sjedinjene Američke Države, 29.07.2012. - 03.08.2012

Vrsta sudjelovanja
Poster

Vrsta recenzije
Međunarodna recenzija

Ključne riječi
superconductivity; fluctuations; cuprates; ac conductivity

Sažetak
The superconducting fluctuation regime in the pseudogap phase of cuprate superconductors has been under extensive investigation for many years. By measuring microwave conductivity (~15 GHz), we have shown that the fluctuation regime of compounds (HgBa2CuO4+δ and YBa2Cu3O6+δ) with high maximal transition temperatures at optimal doping (Tcmax ≈ 93-97 K) is confined to a narrow temperature range, extending just 10-15 K above Tc [1-2]. Recently, THz time-domain spectroscopy (0.2-1.5 THz) on thin films of the low-Tc max compound La2-xSrxCuO4 (Tcmax ≈ 40 K) [3] indicated the presence of fast superconducting fluctuations in a similarly narrow temperature range (10-15 K above Tc). In order to clarify whether the observation of a narrow fluctuation regime is a universal property of the cuprates and not limited to specific compounds or probes, we have studied the microwave conductivity of high-quality, single crystals of La2-xSrxCuO4 and determined the ac conductivity parallel (σab) and perpendicular (σc) to the CuO2 planes. By applying an external magnetic field, we were able to extract the contribution due to superconducting fluctuations. Consistent with the aforementioned studies, the fluctuation regime in bulk single crystals of this low-Tcmax compound is narrow and tracks the superconducting dome. Acknowledgement/Reference: [1] M. S. Grbić et al., Phys. Rev. 80, 094511 (2009). [2] M. S. Grbić et. al., Phys. Rev. B 83, 144508 (2011). [3] L. S. Bilbro, R. Valdés Aguilar, G. Logvenov, O. Pelleg, I. Božović, N. P. Armitage, Nat. Phys. 7, 298 (2011).

Izvorni jezik
Engleski

Znanstvena područja
Fizika

POVEZANOST RADA