Professor Stephen Blundell: Publications

Dynamic Spin Fluctuations in the Frustrated A-site Spinel CuAl2O4

(2020)

Authors:

Hwanbeom Cho, R Nirmala, Jaehong Jeong, Peter J Baker, Hikaru Takeda, Nobuyoshi Mera, Stephen J Blundell, Masashi Takigawa, DT Adroja, Je-Geun Park

Magnetism and Néel skyrmion dynamics in GaV4S8-ySey

Physical Review Research American Physical Society (APS) 2:3 (2020) 032001

Authors:

TJ Hicken, SJR Holt, KJA Franke, Z Hawkhead, A Štefančič, MN Wilson, M Gomilšek, BM Huddart, SJ Clark, MR Lees, FL Pratt, SJ Blundell, G Balakrishnan, T Lancaster

Magnetic order and ballistic spin transport in a sine-Gordon spin chain

(2020)

Authors:

BM Huddart, M Gomilšek, TJ Hicken, FL Pratt, SJ Blundell, PA Goddard, SJ Kaech, JL Manson, T Lancaster

Extremely well isolated 2D spin-$1/2$ antiferromagnetic Heisenberg layers with small exchange coupling in the molecular-based magnet CuPOF

(2020)

Authors:

D Opherden, N Nizar, K Richardson, JC Monroe, MM Turnbull, M Polson, S Vela, WJA Blackmore, PA Goddard, J Singleton, ES Choi, F Xiao, RC Williams, T Lancaster, FL Pratt, SJ Blundell, Y Skourski, M Uhlarz, AN Ponomaryov, SA Zvyagin, J Wosnitza, M Baenitz, I Heinmaa, R Stern, H Kühne, CP Landee

Competing pairing interactions responsible for the large upper critical field in a stoichiometric iron-based superconductor CaKFe4As4

Physical Review B American Physical Society 101 (2020) 134502

Authors:

Matthew Bristow, William Knafo, Pascal Reiss, William Meier, Paul C Canfield, Stephen J Blundell, Amalia Coldea

Abstract:

The upper critical field of multiband superconductors is an important quantity that can reveal details about the nature of the superconducting pairing. Here we experimentally map out the complete upper-critical-field phase diagram of a stoichiometric superconductor, CaKFe4As4, up to 90 T for different orientations of the magnetic field and at temperatures down to 4.2K. The upper critical fields are extremely large, reaching values close to ∼3 Tc at the lowest temperature, and the anisotropy decreases dramatically with temperature, leading to essentially isotropic superconductivity at 4.2K. We find that the temperature dependence of the upper critical field can be well described by a two-band model in the clean limit with band-coupling parameters favoring intraband over interband interactions. The large Pauli paramagnetic effects together with the presence of the shallow bands is consistent with the stabilization of an FFLO state at low temperatures in this clean superconductor.

91̽��