Observation of superluminal geometrical resonances in Bi2Sr2CaCu2O8+x intrinsic Josephson junctions

Abstract

We study Fiske steps in small Bi2Sr2CaCu2O8+x mesa structures, containing only few stacked intrinsic Josephson junctions. Careful alignment of magnetic field prevents penetration of Abrikosov vortices and facilitates observation of a large variety of high quality geometrical resonances, including superluminal with velocities larger than the slowest velocity of electromagnetic waves. A small number of junctions limits the number of resonant modes and allows accurate identification of modes and velocities. It is shown that superluminal geometrical resonances can be excited by subluminal fluxon motion and that flux-flow itself becomes superluminal at high magnetic fields. We argue that observation of high-quality superluminal geometrical resonances is crucial for realization of the coherent flux-flow oscillator in the THz frequency range.

References in corpus (5)

• Mechanism of Terahertz Electromagnetic Wave Emission from Intrinsic Josephson Junctions
• Temperature dependence of the bulk energy gap in underdoped Bi-2212: Evidence for the mean-field superconducting transition
• Quantum cascade phenomenon in natural atomic superlattices formed in Bi2Sr2CaCu2O8 single crystals
• Stabilization of in-phase fluxon state by geometrical confinement in small Bi-2212 mesa structures
• Collective Josephson vortex dynamics in a finite number of intrinsic Josephson junctions

Cited by in corpus (11)

• THz emission from intrinsic Josephson junctions at zero magnetic field via breather auto-oscillations
• THz emission from a stacked coherent flux-flow oscillator: non-local radiative boundary conditions and the role of geometrical resonances
• Thermal and electromagnetic properties of Bi${}_2$Sr${}_2$CaCu${}_2$O${}_8$ intrinsic Josephson junction stacks studied via one-dimensional coupled sine-Gordon equations
• Observation of polaritons in Bi2Sr2CaCu2O8+x single crystals
• Design aspects of Bi${}_2$Sr${}_2$CaCu${}_2$O${}_{8+\delta }$ THz sources: optimization of thermal and radiative properties
• Persistent electrical doping of Bi2Sr2CaCu2O8+x mesa structures
• Low anisotropy of the upper critical field in a strongly anisotropic layered cuprate: Evidence for paramagnetically limited superconductivity
• Thick Bi2Sr2CaCu2O8+δ films grown by liquid-phase epitaxy for Josephson THz applications
• "Quick and dirty" technology for fabrication of a single BiSrCaCuO mesas
• A distributed, active patch antenna model of a Josephson oscillator
• Strong polaritonic interaction between flux-flow and phonon resonances in Bi2Sr2CaCu2O8+x intrinsic Josephson junctions: Angular dependence and the alignment procedure