Synthesized complex-frequency excitation for ultrasensitive molecular sensing

eLight, Journal Year: 2024, Volume and Issue: 4(1)

Published: Jan. 5, 2024

Abstract Sensors have emerged as indispensable analytical tools across a wide range of important fields, encompassing environmental monitoring, food safety, and public health. They facilitate early disease diagnosis, personalized medicine, rapid detection toxic agents. However, detecting trace molecules remains significant challenge. Surface-enhanced infrared absorption (SEIRA) based on plasmonic nanostructures, particularly graphene, has promising approach to enhance sensing sensitivity. While graphene-based SEIRA offers advantages such high sensitivity active tunability, intrinsic molecular damping weakens the interaction between vibrational modes plasmons. Here, we demonstrate ultrahigh-sensitive synthesized complex-frequency waves (CFW). Our experiment shows that CFW can amplify signals (silk protein monolayer) detected by sensor at least an order magnitude be universally applied in different phases. is highly scalable investigation light-matter interactions, enabling diverse potential applications fields optical spectroscopy, biomedicine pharmaceutics.

Language: Английский

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Polarization-independent high-sensitive metamaterial sensor for chemical sensing and EMI shielding application

Engineering Science and Technology an International Journal, Journal Year: 2025, Volume and Issue: 62, P. 101952 - 101952

Published: Jan. 28, 2025

Language: Английский

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Efficient excitation and control of integrated photonic circuits with virtual critical coupling

Nature Communications, Journal Year: 2024, Volume and Issue: 15(1)

Published: March 28, 2024

Abstract Critical coupling in integrated photonic devices enables the efficient transfer of energy from a waveguide to resonator, key operation for many applications. This condition is achieved when resonator loss rate equal bus waveguide. Carefully matching these quantities challenging practice, due variations properties resulting fabrication and external conditions. Here, we demonstrate that non-critically coupled can be by tailoring excitation signal time. We rely on excitations oscillating at complex frequencies load an otherwise overcoupled demonstrating virtual critical if imaginary part frequency equals mismatch between rate. probe microring with tailored pulses observe minimum intensity transmission $$T=0.11$$ T = 0.11 contrast continuous-wave $$T=0.58$$ 0.58 , corresponding 8 times enhancement intracavity intensity. Our technique opens opportunities enhancing controlling on-demand light-matter interactions linear nonlinear platforms.

Language: Английский

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Higher-order skin effect and its observation in an acoustic kagome lattice

Physical review. B./Physical review. B, Journal Year: 2025, Volume and Issue: 111(1)

Published: Jan. 23, 2025

Language: Английский

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Gain–loss coupled systems

Deleted Journal, Journal Year: 2025, Volume and Issue: 2(1)

Published: Feb. 18, 2025

Achieving oscillations with small dimensions, high power, coherence, and low phase noise has been a long-standing goal in wave physics, driving innovations across classical electromagnetic theory quantum physics. Key applications include electronic oscillators, lasers, spin-torque oscillations. In recent decades, physicists have increasingly focused on harnessing passive oscillatory modes to manipulate these oscillations, leading the development of diverse gain–loss coupled systems, including photon–photon, exciton–photon, photon–magnon, magnon–phonon, magnon–magnon couplings. This review provides comprehensive overview exploring their fundamental physical structures, key experimental observations, theoretical insights. By synthesizing insights from studies, we propose future research directions further advance understanding application systems for science technologies.

Language: Английский

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Exact Maxwell evolution equation of resonator dynamics: temporal coupled-mode theory revisited

Optics Express, Journal Year: 2024, Volume and Issue: 32(12), P. 20904 - 20904

Published: May 2, 2024

Despite its widespread significance, the temporal coupled-mode theory (CMT) lacks a foundational validation based on electromagnetic principles and stands as phenomenological relying fitted coupling coefficients. We employ an ab initio Maxwellian approach using quasinormal-mode to derive “exact” Maxwell evolution (EME) equation for resonator dynamics. While resulting differential bears resemblance classical one, it introduces novel terms embodying distinct physics, suggesting that CMT predictions could be faulted by dedicated experiments, instance carried out with short off-resonance pulses, or resonators of sizes comparable greater than wavelength. Nonetheless, our examination indicates that, despite inherent lack strictness, enables precise numerous experiments due flexibility provided The new EME is anticipated applicable all geometries, theoretical we have taken can extended other wave physics.

Language: Английский

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Theory of stochastic resonance with state-dependent diffusion

Physical review. E, Journal Year: 2025, Volume and Issue: 111(1)

Published: Jan. 10, 2025

Several interesting and important natural processes are the manifestation of interplay nonlinearity fluctuations. Stochastic resonance is one such mechanism crucial to explain many physical, chemical, biological processes, as well having huge technological importance. The general setup describe stochastic considers two states. Recently, it has been unveiled that necessary consider intrinsic fluctuations related different states system in interpreting certain fundamental glacial-interglacial transitions Earth's ice age. This also significance developing advantageous technologies. However, until now, there no theory describing terms transition rate between their probability distribution function while considering noise amplitudes or fluctuation characteristics these development this attempted present research work. As a first step, relevant approximation used which considered within adiabatic limit. analytical derivations corroborated by numerical simulation results. Furthermore, semianalytical proposed for definite without any approximations exact solution not achievable. found replicate results obtained from Brownian dynamics study previously known quantifiers estimated context with state-dependent diffusion.

Language: Английский

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Complex-frequency calculation in acoustics with real-frequency solvers

Physical review. B./Physical review. B, Journal Year: 2025, Volume and Issue: 111(2)

Published: Jan. 16, 2025

Complex-frequency calculation enables the characterization of open wave systems in complex frequency plane as well evaluation behaviors under virtual gain and/or loss, which has widespread applications investigations scattering and non-Hermitian physics. The corresponding approaches, however, have not been developed are usually limited to simple analytical models. Here, we report an efficient numerical method for calculating complex-frequency acoustic fields, imaginary part is equivalently converted into variation material parameters. In this way, problem becomes a real-frequency one can then be readily implemented with most existing solvers Helmholtz equation. proposed validated by considering two representative examples: one-port lossy resonator imaging superlens excitation. Our work provides practical general solution calculation, principle, applicable any complex, dispersive systems, could serve powerful tool fundamental applied research related non-Hermiticity. locked icon Physics Subject Headings (PhySH)Acoustic metamaterialsAcoustic modelingAcoustic phenomenaAcousticsNon-Hermitian

Language: Английский

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Non-Hermitian physics of evanescent waves around band singularities

Physical review. B./Physical review. B, Journal Year: 2025, Volume and Issue: 111(10)

Published: March 21, 2025

Language: Английский

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Complex-frequency excitations in photonics and wave physics

Science, Journal Year: 2025, Volume and Issue: 387(6741)

Published: March 27, 2025

Closed, lossless optical cavities are characterized by a Hamiltonian that obeys Hermiticity, resulting in strictly real-valued resonance frequencies. By contrast, non-Hermitian wave systems Hamiltonians with poles and zeros at complex frequencies, whose control through precise engineering of material loss gain can lead to exotic scattering phenomena. Notably, excitation signals oscillate complex-valued frequencies mimic the emergence loss, facilitating access these responses without modifications. These findings have been advancing fundamental understanding wave-matter interactions enabling breakthroughs metamaterials, imaging, sensing, computing. This Review examines theoretical advances experimental discoveries this emerging field, demonstrating how tailored time-domain excitations offer new opportunities for manipulation control.

Language: Английский

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