Explore the vast range of titles available.

Hybrid van der Waals heterostructures that combine topological insulators with high‐temperature superconductors offer a promising platform for tunable terahertz (THz) photonics compatible with cryogenic quantum technologies. We present a theoretical and numerical study of ultrafast THz modulation in proximitized (Bi2‐xInx)Se3 interfaced with Bi2Sr2CaCu2O8+δ. Indium‐driven topological phase transitions enable selective control of THz transmission, yielding a tuning depth of 23.8% and a resonance shift of 111 GHz. Under ultrafast optical excitation, the hybrid system reaches a modulation depth of 30.4%, a frequency shift of 52 GHz, and a group delay of 0.71 ps. These results provide a design framework for topological–superconducting metamaterials and indicate their potential for dynamic THz control in quantum photonic architectures. Hybrid van der Waals topological–superconducting heterostructures enable cryogenically compatible, highly tunable THz photonic circuits. We model ultrafast THz modulation in proximitized (Bi2‐xInx)Se3–BSCCO devices, capturing indium‐driven topological phase transitions and ultrafast superconductor dynamics. The system delivers up to 30% modulation depth, >100 GHz frequency tuning, and sub‐picosecond delays, paving the way toward ultrafast THz quantum technologies.

Metamaterial photonic integrated circuits with arrays of hybrid graphene–superconductor coupled split-ring resonators (SRR) capable of modulating and slowing down terahertz (THz) light are introduced and proposed. The hybrid device’s optical responses, such as electromagnetic-induced transparency (EIT) and group delay, can be modulated in several ways. First, it is modulated electrically by changing the conductivity and carrier concentrations in graphene. Alternatively, the optical response can be modified by acting on the device temperature sensitivity by switching Nb from a lossy normal phase to a low-loss quantum mechanical phase below the transition temperature (Tc) of Nb. Maximum modulation depths of 57.3% and 97.61% are achieved for EIT and group delay at the THz transmission window, respectively. A comparison is carried out between the Nb-graphene-Nb coupled SRR-based devices with those of Au-graphene-Au SRRs, and significant enhancements of the THz transmission, group delay, and EIT responses are observed when Nb is in the quantum mechanical phase. Such hybrid devices with their reasonably large and tunable slow light bandwidth pave the way for the realization of active optoelectronic modulators, filters, phase shifters, and slow light devices for applications in chip-scale future communication and computation systems.

Ultrafast Terahertz Dynamics in Hybrid van der Waals Superconductor This research investigate ultrafast THz pulses interaction with hybrid superconductor–topological insulator metamaterials, enabling dynamic conductivity control through indium‐driven topological transitions and proximity‐induced superconductivity. More details can be found in the Research Article by Samane Kalhor and Kaveh Delfanazari (DOI: 10.1002/adpr.202500195).

We produced NiFeMo ribbons by electrodeposition technique under applied currents ranging from 40 to 240 mA. The SEM analysis showed a uniform and crack-free coating. Then, we measured the transverse and longitudinal magnetoimpedance of ribbons. We also obtained the hysteresis loops of the ribbons by means of magnetooptical Kerr effect to investigate their magnetic properties. The result showed that the increase in deposition current density caused a decline in the magnetic softness of the ribbons so that some of the ribbons exhibited an exchange spring effect. The magnetic hardening also caused a reduction in the magnetoimpedance response. We also theoretically calculated the susceptibility of a ribbon by considering the random magnetic anisotropy. The multi-peak behavior of susceptibility is in agreement with the multi-peak behavior of magnetoimpedance.

Plasmonics, as a rapidly growing research field, provides new pathways to guide and modulate highly confined light in the microwave-to-optical range of frequencies. We demonstrated a plasmonic slot waveguide, at the nanometer scale, based on the high-transition-temperature (Tc) superconductor Bi2Sr2CaCu2O8+δ (BSCCO), to facilitate the manifestation of chip-scale millimeter wave (mm-wave)-to-terahertz (THz) integrated circuitry operating at cryogenic temperatures. We investigated the effect of geometrical parameters on the modal characteristics of the BSCCO plasmonic slot waveguide between 100 and 800 GHz. In addition, we investigated the thermal sensing of the modal characteristics of the nanoscale superconducting slot waveguide and showed that, at a lower frequency, the fundamental mode of the waveguide had a larger propagation length, a lower effective refractive index, and a strongly localized modal energy. Moreover, we found that our device offered a larger SPP propagation length and higher field confinement than the gold plasmonic waveguides at broad temperature ranges below BSCCO’s Tc. The proposed device can provide a new route toward realizing cryogenic low-loss photonic integrated circuitry at the nanoscale.

Advancing large-scale quantum computing requires superconducting circuits that combine long coherence times with compatibility with semiconductor technology. We investigate niobium nitride (NbN) coplanar waveguide resonators integrated with Si/SiGe quantum wells, creating a hybrid platform designed for CMOS-compatible quantum hardware. Using temperature-dependent microwave spectroscopy in the single-photon regime, we examine resonance frequency and quality factor variations to probe the underlying loss mechanisms. Our analysis identifies the roles of two-level systems, quasiparticles, and scattering processes, and connects these losses to wafer properties and fabrication methods. The devices demonstrate reproducible performance and stable operation maintained for over two years, highlighting their robustness. These results provide design guidelines for developing low-loss, CMOS-compatible superconducting circuits and support progress toward resilient, scalable architectures for quantum information processing.

Metamaterial photonic integrated circuits with arrays of hybrid graphene-superconductor coupled split-ring resonators (SRR) capable of modulating and slowing down terahertz (THz) light are introduced and proposed. The hybrid device optical responses, such as electromagnetic induced transparency (EIT) and group delay, can be modulated in several ways. First, it is modulated electrically by changing the conductivity and carrier concentrations in graphene. Alternatively, the optical response can be modified by acting on the device temperature sensitivity, by switching Nb from a lossy normal phase to a low-loss quantum mechanical phase below the transition temperature (Tc) of Nb. Maximum modulation depths of 57.3 % and 97.61 % are achieved for EIT and group delay at the THz transmission window, respectively. A comparison is carried out between the Nb-graphene-Nb coupled SRR-based devices with those of Au-graphene-Au SRRs and a significant enhancement of the THz transmission, group delay, and EIT responses are observed when Nb is in the quantum mechanical phase. Such hybrid devices with their reasonably large and tunable slow light bandwidth pave the way for the realization of active optoelectronic modulators, filters, phase shifters, and slow light devices for applications in chip-scale quantum communication and quantum processing.