Hot spots and waves in Bi2Sr2CaCu2O8 intrinsic Josephson junction stacks -a study by Low Temperature Scanning Laser Microscopy

TL;DR

This study uses Low Temperature Scanning Laser Microscopy to image electric field distributions in Bi2Sr2CaCu2O8 Josephson junction stacks, revealing cavity modes and hot spot interactions that may enable new THz radiation generation methods.

Contribution

It demonstrates the formation of standing-wave patterns through hot spot interactions, suggesting a novel mode for synchronized THz emission in Josephson junction stacks.

Findings

Cavity modes are observed at low bias.

Hot spots influence standing-wave formation.

Potential new mode for THz generation identified.

Abstract

Recently, it has been shown that large stacks of intrinsic Josephson junctions in Bi2Sr2CaCu2O8 emit synchronous THz radiation, the synchronization presumably triggered by a cavity resonance. To investigate this effect we use Low Temperature Scanning Laser Microscopy to image electric field distributions. Apart from verifying the appearance of cavity modes at low bias we find that, in a high input power regime, standing-wave patterns are created through interactions with a hot spot, possibly pointing to a new mode of generating synchronized radiation in intrinsic Josephson junction stacks.