Zero-Field Fiske Resonance Coupled with Spin-Waves in Ferromagnetic Josephson Junctions

Abstract

AC Josephson current density in a Josephson junction with DC bias is spatially modulatedby an external magnetic field, and induces an electromagnetic (EM) field inside the junction.The current-voltage (I-V ) curve exhibits peaks due to the resonance between the EM field and the spatially modulated AC Josephson current density. This is called Fiske resonance.Such a spatially modulated Josephson current density can be also induced by a non-uniform insulating barrier and the Fiske resonance appears without external magnetic field. This is called zero-field Fiske resonance (ZFFR). In this paper, we theoretically study the ZFFR coupled with spin-waves in a superconductor/ferromagnetic insulator/superconductor junction (ferromagnetic Josephson junction) with a non-uniform ferromagnetic insulating barrier.The resonant mode coupled with spin-waves can be induced without external magnetic field.We find that the I-V curve shows resonant peaks associated with composite excitations of spin-waves and the EM field in the junction. The voltage at the resonance is obtained as a function of the normal modes of EM field. The ZFFRs coupled with spin-waves are found as peak structures in the DC Josephson current density as a function of bias voltage.

Triplet Superconducting Correlations in Hybrid Superconducting Junctions

“…Note, in our experiment conditions the level of applied magnetic field H was much smaller than that, required for Zeeman splitting. At the same time another interesting feature (will be discussed below) has been revealed in our experiment, which hints on possible influence of magnon-plasma wave interaction [84,85].…”

“…However, predicted deviations from ordinary theory [94] were not observed on S/IF/S structures in experiments [95,96]. At the same time, the existence of strong SOI, which was not taken in-to account [84,85], but exist in discussed S-MS structures may dramatically change high frequency the dynamics of electromagnetic waves propagation in Josephson strictures with magnetic barriers.…”

“…From these data we estimated q =0.13 in C-MS. High frequency dynamics of Josephson junctions with magnetic barriers depends also on propagation of electromagnetic waves. The influence of magnetic characteristics of Josephson junction barrier was considered and theoretically analyzed for S/I/F/S and S/F/I/F/S structures [84], as well for S/IF/S [85], where F is a ferromagnet, and IF is a ferromagnetic insulator. However, predicted deviations from ordinary theory [94] were not observed on S/IF/S structures in experiments [95,96].…”

Collective magnetic and plasma excitations in Josephson $ψ$ junctions

“…22 Experimentally, the hybridized waves are expected to reveal themselves mainly through substantial changes in the number, position and shape of Fiske and Shapiro steps on the I-V characteristics of S/F/S junctions. [22][23][24][25][26][27][28][29][30][31][32] Another remarkable manifestation of such coupling between plasma-like and spin waves is the possibility to stimulate the magnetization reversal in the F layer by applying the current through the junction. 24,[33][34][35][36] This may provide the effective mechanism of the magnetic moment control in the devices of superconducting spintronics.…”

Heat transport and electron cooling in ballistic normal-metal/spin-filter/superconductor junctions

“…Recently, influences of the spin-filter effect in ferromagnetic-semiconductors [12][13][14] on the proximity effect [15][16][17][18][19][20][21], the Josephson effect [22][23][24][25][26][27][28][29][30][31][32], and macroscopic quantum phenomena [33][34][35][36] have been investigated theoretically. Moreover, superconducting tunnel junctions with spin-filters have been also realized experimentally [37][38][39][40] In this work we propose an novel electron-cooler based on clean N/spin-filter/S junctions [see Fig.…”