2018/08/24 by Emanuel Mompó, Emanuel Mompo, Miguel Ruiz Garcia +7 · 2 citations
Physics and Astronomy · #Atomic physics #Coherence (philosophical gambling strategy) #Condensed matter physics #Dipole #Noise (video) #Oscillation (cell signaling) #Physics #Quantum and electron transport phenomena #Quantum mechanics #Resonance (particle physics) #Semiconductor Quantum Structures and Devices #Stochastic resonance #Superlattice #cond-mat.mes-hall #cond-mat.stat-mech #stochastic dynamics and bifurcation
paper · pdf · doi:10.1103/physrevlett.121.086805
published as Physical Review Letters 121, 086805 (2018) · 21 pages, 12 figures, preprint version including suppl. material
openalex publication_date 2018/08/24 · arxiv created 2020/11/18 · arxiv updated 2020/11/19 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
Collective electron transport causes a weakly coupled semiconductor superlattice under dc voltage bias to be an excitable system with 2N+2 degrees of freedom: electron densities and fields at N superlattice periods plus the total current and the field at the injector. External noise of sufficient amplitude induces regular current self-oscillations (coherence resonance) in states that are stationary in the absence of noise. Numerical simulations show that these oscillations are due to the repeated nucleation and motion of charge dipole waves that form at the emitter when the current falls below a critical value. At the critical current, the well-to-well tunneling current intersects the contact load line. We have determined the device-dependent critical current for the coherence resonance from experiments and numerical simulations. We have also described through numerical simulations how a coherence resonance triggers a stochastic resonance when its oscillation mode becomes locked to a weak ac external voltage signal. Our results agree with the experimental observations.